Data items in the ATOM_SITE category record details about the atom sites in a macromolecular crystal structure, such as the positional coordinates, atomic displacement parameters, magnetic moments and directions, and so on. The data items for describing anisotropic temperature or atomic displacement factors are only used if the corresponding items are not given in the ATOM_SITE_ANISOTROP category. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:atom_siteCategory> <RCSB:atom_site id="1"> <RCSB:B_iso_or_equiv>17.93</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>25.369</RCSB:Cartn_x> <RCSB:Cartn_y>30.691</RCSB:Cartn_y> <RCSB:Cartn_z>11.795</RCSB:Cartn_z> <RCSB:auth_seq_id>11</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>N</RCSB:label_atom_id> <RCSB:label_comp_id>VAL</RCSB:label_comp_id> <RCSB:label_seq_id>11</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>N</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="2"> <RCSB:B_iso_or_equiv>17.75</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>25.970</RCSB:Cartn_x> <RCSB:Cartn_y>31.965</RCSB:Cartn_y> <RCSB:Cartn_z>12.332</RCSB:Cartn_z> <RCSB:auth_seq_id>11</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>CA</RCSB:label_atom_id> <RCSB:label_comp_id>VAL</RCSB:label_comp_id> <RCSB:label_seq_id>11</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="3"> <RCSB:B_iso_or_equiv>17.83</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>25.569</RCSB:Cartn_x> <RCSB:Cartn_y>32.010</RCSB:Cartn_y> <RCSB:Cartn_z>13.808</RCSB:Cartn_z> <RCSB:auth_seq_id>11</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>C</RCSB:label_atom_id> <RCSB:label_comp_id>VAL</RCSB:label_comp_id> <RCSB:label_seq_id>11</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="4"> <RCSB:B_iso_or_equiv>17.53</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>24.735</RCSB:Cartn_x> <RCSB:Cartn_y>31.190</RCSB:Cartn_y> <RCSB:Cartn_z>14.167</RCSB:Cartn_z> <RCSB:auth_seq_id>11</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>O</RCSB:label_atom_id> <RCSB:label_comp_id>VAL</RCSB:label_comp_id> <RCSB:label_seq_id>11</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>O</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="5"> <RCSB:B_iso_or_equiv>17.66</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>25.379</RCSB:Cartn_x> <RCSB:Cartn_y>33.146</RCSB:Cartn_y> <RCSB:Cartn_z>11.540</RCSB:Cartn_z> <RCSB:auth_seq_id>11</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>CB</RCSB:label_atom_id> <RCSB:label_comp_id>VAL</RCSB:label_comp_id> <RCSB:label_seq_id>11</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="6"> <RCSB:B_iso_or_equiv>18.86</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>25.584</RCSB:Cartn_x> <RCSB:Cartn_y>33.034</RCSB:Cartn_y> <RCSB:Cartn_z>10.030</RCSB:Cartn_z> <RCSB:auth_seq_id>11</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>CG1</RCSB:label_atom_id> <RCSB:label_comp_id>VAL</RCSB:label_comp_id> <RCSB:label_seq_id>11</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="7"> <RCSB:B_iso_or_equiv>17.12</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>23.933</RCSB:Cartn_x> <RCSB:Cartn_y>33.309</RCSB:Cartn_y> <RCSB:Cartn_z>11.872</RCSB:Cartn_z> <RCSB:auth_seq_id>11</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>CG2</RCSB:label_atom_id> <RCSB:label_comp_id>VAL</RCSB:label_comp_id> <RCSB:label_seq_id>11</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="8"> <RCSB:B_iso_or_equiv>18.97</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>26.095</RCSB:Cartn_x> <RCSB:Cartn_y>32.930</RCSB:Cartn_y> <RCSB:Cartn_z>14.590</RCSB:Cartn_z> <RCSB:auth_seq_id>12</RCSB:auth_seq_id> <RCSB:footnote_id>4</RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>N</RCSB:label_atom_id> <RCSB:label_comp_id>THR</RCSB:label_comp_id> <RCSB:label_seq_id>12</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>N</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="9"> <RCSB:B_iso_or_equiv>19.80</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>25.734</RCSB:Cartn_x> <RCSB:Cartn_y>32.995</RCSB:Cartn_y> <RCSB:Cartn_z>16.032</RCSB:Cartn_z> <RCSB:auth_seq_id>12</RCSB:auth_seq_id> <RCSB:footnote_id>4</RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>CA</RCSB:label_atom_id> <RCSB:label_comp_id>THR</RCSB:label_comp_id> <RCSB:label_seq_id>12</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="10"> <RCSB:B_iso_or_equiv>20.92</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>24.695</RCSB:Cartn_x> <RCSB:Cartn_y>34.106</RCSB:Cartn_y> <RCSB:Cartn_z>16.113</RCSB:Cartn_z> <RCSB:auth_seq_id>12</RCSB:auth_seq_id> <RCSB:footnote_id>4</RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>C</RCSB:label_atom_id> <RCSB:label_comp_id>THR</RCSB:label_comp_id> <RCSB:label_seq_id>12</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="11"> <RCSB:B_iso_or_equiv>21.84</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>24.869</RCSB:Cartn_x> <RCSB:Cartn_y>35.118</RCSB:Cartn_y> <RCSB:Cartn_z>15.421</RCSB:Cartn_z> <RCSB:auth_seq_id>12</RCSB:auth_seq_id> <RCSB:footnote_id>4</RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>O</RCSB:label_atom_id> <RCSB:label_comp_id>THR</RCSB:label_comp_id> <RCSB:label_seq_id>12</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>O</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="12"> <RCSB:B_iso_or_equiv>20.51</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>26.911</RCSB:Cartn_x> <RCSB:Cartn_y>33.346</RCSB:Cartn_y> <RCSB:Cartn_z>17.018</RCSB:Cartn_z> <RCSB:auth_seq_id>12</RCSB:auth_seq_id> <RCSB:footnote_id>4</RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>CB</RCSB:label_atom_id> <RCSB:label_comp_id>THR</RCSB:label_comp_id> <RCSB:label_seq_id>12</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="13"> <RCSB:B_iso_or_equiv>20.29</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>27.946</RCSB:Cartn_x> <RCSB:Cartn_y>33.921</RCSB:Cartn_y> <RCSB:Cartn_z>16.183</RCSB:Cartn_z> <RCSB:auth_seq_id>12</RCSB:auth_seq_id> <RCSB:footnote_id>4</RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id>3</RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>OG1</RCSB:label_atom_id> <RCSB:label_comp_id>THR</RCSB:label_comp_id> <RCSB:label_seq_id>12</RCSB:label_seq_id> <RCSB:occupancy>0.50</RCSB:occupancy> <RCSB:type_symbol>O</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="14"> <RCSB:B_iso_or_equiv>20.59</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>27.769</RCSB:Cartn_x> <RCSB:Cartn_y>32.142</RCSB:Cartn_y> <RCSB:Cartn_z>17.103</RCSB:Cartn_z> <RCSB:auth_seq_id>12</RCSB:auth_seq_id> <RCSB:footnote_id>4</RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id>4</RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>OG1</RCSB:label_atom_id> <RCSB:label_comp_id>THR</RCSB:label_comp_id> <RCSB:label_seq_id>12</RCSB:label_seq_id> <RCSB:occupancy>0.50</RCSB:occupancy> <RCSB:type_symbol>O</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="15"> <RCSB:B_iso_or_equiv>20.47</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>27.418</RCSB:Cartn_x> <RCSB:Cartn_y>32.181</RCSB:Cartn_y> <RCSB:Cartn_z>17.878</RCSB:Cartn_z> <RCSB:auth_seq_id>12</RCSB:auth_seq_id> <RCSB:footnote_id>4</RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id>3</RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>CG2</RCSB:label_atom_id> <RCSB:label_comp_id>THR</RCSB:label_comp_id> <RCSB:label_seq_id>12</RCSB:label_seq_id> <RCSB:occupancy>0.50</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="16"> <RCSB:B_iso_or_equiv>20.00</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>26.489</RCSB:Cartn_x> <RCSB:Cartn_y>33.778</RCSB:Cartn_y> <RCSB:Cartn_z>18.426</RCSB:Cartn_z> <RCSB:auth_seq_id>12</RCSB:auth_seq_id> <RCSB:footnote_id>4</RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id>4</RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>CG2</RCSB:label_atom_id> <RCSB:label_comp_id>THR</RCSB:label_comp_id> <RCSB:label_seq_id>12</RCSB:label_seq_id> <RCSB:occupancy>0.50</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="17"> <RCSB:B_iso_or_equiv>22.08</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>23.664</RCSB:Cartn_x> <RCSB:Cartn_y>33.855</RCSB:Cartn_y> <RCSB:Cartn_z>16.884</RCSB:Cartn_z> <RCSB:auth_seq_id>13</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>N</RCSB:label_atom_id> <RCSB:label_comp_id>ILE</RCSB:label_comp_id> <RCSB:label_seq_id>13</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>N</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="18"> <RCSB:B_iso_or_equiv>23.44</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>22.623</RCSB:Cartn_x> <RCSB:Cartn_y>34.850</RCSB:Cartn_y> <RCSB:Cartn_z>17.093</RCSB:Cartn_z> <RCSB:auth_seq_id>13</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>CA</RCSB:label_atom_id> <RCSB:label_comp_id>ILE</RCSB:label_comp_id> <RCSB:label_seq_id>13</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="19"> <RCSB:B_iso_or_equiv>25.77</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>22.657</RCSB:Cartn_x> <RCSB:Cartn_y>35.113</RCSB:Cartn_y> <RCSB:Cartn_z>18.610</RCSB:Cartn_z> <RCSB:auth_seq_id>13</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>C</RCSB:label_atom_id> <RCSB:label_comp_id>ILE</RCSB:label_comp_id> <RCSB:label_seq_id>13</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="20"> <RCSB:B_iso_or_equiv>26.28</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>23.123</RCSB:Cartn_x> <RCSB:Cartn_y>34.250</RCSB:Cartn_y> <RCSB:Cartn_z>19.406</RCSB:Cartn_z> <RCSB:auth_seq_id>13</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>O</RCSB:label_atom_id> <RCSB:label_comp_id>ILE</RCSB:label_comp_id> <RCSB:label_seq_id>13</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>O</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="21"> <RCSB:B_iso_or_equiv>22.67</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>21.236</RCSB:Cartn_x> <RCSB:Cartn_y>34.463</RCSB:Cartn_y> <RCSB:Cartn_z>16.492</RCSB:Cartn_z> <RCSB:auth_seq_id>13</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>CB</RCSB:label_atom_id> <RCSB:label_comp_id>ILE</RCSB:label_comp_id> <RCSB:label_seq_id>13</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="22"> <RCSB:B_iso_or_equiv>22.14</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>20.478</RCSB:Cartn_x> <RCSB:Cartn_y>33.469</RCSB:Cartn_y> <RCSB:Cartn_z>17.371</RCSB:Cartn_z> <RCSB:auth_seq_id>13</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>CG1</RCSB:label_atom_id> <RCSB:label_comp_id>ILE</RCSB:label_comp_id> <RCSB:label_seq_id>13</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="23"> <RCSB:B_iso_or_equiv>21.75</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>21.357</RCSB:Cartn_x> <RCSB:Cartn_y>33.986</RCSB:Cartn_y> <RCSB:Cartn_z>15.016</RCSB:Cartn_z> <RCSB:auth_seq_id>13</RCSB:auth_seq_id> <RCSB:footnote_id></RCSB:footnote_id> <RCSB:group_PDB>ATOM</RCSB:group_PDB> <RCSB:label_alt_id></RCSB:label_alt_id> <RCSB:label_asym_id>A</RCSB:label_asym_id> <RCSB:label_atom_id>CG2</RCSB:label_atom_id> <RCSB:label_comp_id>ILE</RCSB:label_comp_id> <RCSB:label_seq_id>13</RCSB:label_seq_id> <RCSB:occupancy>1.00</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="101"> <RCSB:B_iso_or_equiv>17.27</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>4.171</RCSB:Cartn_x> <RCSB:Cartn_y>29.012</RCSB:Cartn_y> <RCSB:Cartn_z>7.116</RCSB:Cartn_z> <RCSB:auth_seq_id>300</RCSB:auth_seq_id> <RCSB:footnote_id>1</RCSB:footnote_id> <RCSB:group_PDB>HETATM</RCSB:group_PDB> <RCSB:label_alt_id>1</RCSB:label_alt_id> <RCSB:label_asym_id>C</RCSB:label_asym_id> <RCSB:label_atom_id>C1</RCSB:label_atom_id> <RCSB:label_comp_id>APS</RCSB:label_comp_id> <RCSB:label_seq_id></RCSB:label_seq_id> <RCSB:occupancy>0.58</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="102"> <RCSB:B_iso_or_equiv>16.95</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>4.949</RCSB:Cartn_x> <RCSB:Cartn_y>27.758</RCSB:Cartn_y> <RCSB:Cartn_z>6.793</RCSB:Cartn_z> <RCSB:auth_seq_id>300</RCSB:auth_seq_id> <RCSB:footnote_id>1</RCSB:footnote_id> <RCSB:group_PDB>HETATM</RCSB:group_PDB> <RCSB:label_alt_id>1</RCSB:label_alt_id> <RCSB:label_asym_id>C</RCSB:label_asym_id> <RCSB:label_atom_id>C2</RCSB:label_atom_id> <RCSB:label_comp_id>APS</RCSB:label_comp_id> <RCSB:label_seq_id></RCSB:label_seq_id> <RCSB:occupancy>0.58</RCSB:occupancy> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="103"> <RCSB:B_iso_or_equiv>16.85</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>4.800</RCSB:Cartn_x> <RCSB:Cartn_y>26.678</RCSB:Cartn_y> <RCSB:Cartn_z>7.393</RCSB:Cartn_z> <RCSB:auth_seq_id>300</RCSB:auth_seq_id> <RCSB:footnote_id>1</RCSB:footnote_id> <RCSB:group_PDB>HETATM</RCSB:group_PDB> <RCSB:label_alt_id>1</RCSB:label_alt_id> <RCSB:label_asym_id>C</RCSB:label_asym_id> <RCSB:label_atom_id>O3</RCSB:label_atom_id> <RCSB:label_comp_id>APS</RCSB:label_comp_id> <RCSB:label_seq_id></RCSB:label_seq_id> <RCSB:occupancy>0.58</RCSB:occupancy> <RCSB:type_symbol>O</RCSB:type_symbol> </RCSB:atom_site> <RCSB:atom_site id="104"> <RCSB:B_iso_or_equiv>16.43</RCSB:B_iso_or_equiv> <RCSB:Cartn_x>5.930</RCSB:Cartn_x> <RCSB:Cartn_y>27.841</RCSB:Cartn_y> <RCSB:Cartn_z>5.869</RCSB:Cartn_z> <RCSB:auth_seq_id>300</RCSB:auth_seq_id> <RCSB:footnote_id>1</RCSB:footnote_id> <RCSB:group_PDB>HETATM</RCSB:group_PDB> <RCSB:label_alt_id>1</RCSB:label_alt_id> <RCSB:label_asym_id>C</RCSB:label_asym_id> <RCSB:label_atom_id>N4</RCSB:label_atom_id> <RCSB:label_comp_id>APS</RCSB:label_comp_id> <RCSB:label_seq_id></RCSB:label_seq_id> <RCSB:occupancy>0.58</RCSB:occupancy> <RCSB:type_symbol>N</RCSB:type_symbol> </RCSB:atom_site> </RCSB:atom_siteCategory> Equivalent isotropic atomic displacement parameter, B~equiv~, in angstroms squared, calculated as the geometric mean of the anisotropic atomic displacement parameters. B~equiv~ = (B~i~ B~j~ B~k~)^1/3^ B~n~ = the principal components of the orthogonalised B^ij^ The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute B_equiv_geom_mean in category atom_site. Isotropic temperature factor parameter, or equivalent isotropic temperature factor, B~equiv~, calculated from anisotropic temperature factor parameters. B~equiv~ = (1/3) sum~i~[sum~j~(B~ij~ A~i~ A~j~ a*~i~ a*~j~)] A = the real space cell lengths a* = the reciprocal space cell lengths B~ij~ = 8 pi^2^ U~ij~ Ref: Fischer, R. X. & Tillmanns, E. (1988). Acta Cryst. C44, 775-776. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute B_iso_or_equiv in category atom_site. The x atom site coordinate in angstroms specified according to a set of orthogonal Cartesian axes related to the cell axes as specified by the description given in attribute Cartn_transform_axes in category atom_sites. The estimated standard deviation of attribute Cartn_x in category atom_site. The y atom site coordinate in angstroms specified according to a set of orthogonal Cartesian axes related to the cell axes as specified by the description given in attribute Cartn_transform_axes in category atom_sites. The estimated standard deviation of attribute Cartn_y in category atom_site. The z atom site coordinate in angstroms specified according to a set of orthogonal Cartesian axes related to the cell axes as specified by the description given in attribute Cartn_transform_axes in category atom_sites. The estimated standard deviation of attribute Cartn_z in category atom_site. Equivalent isotropic atomic displacement parameter, U~equiv~, in angstroms squared, calculated as the geometric mean of the anisotropic atomic displacement parameters. U~equiv~ = (U~i~ U~j~ U~k~)^1/3^ U~n~ = the principal components of the orthogonalised U~ij~ The estimated standard deviation of attribute U_equiv_geom_mean in category atom_site. Isotropic atomic displacement parameter, or equivalent isotropic atomic displacement parameter, U~equiv~, calculated from anisotropic atomic displacement parameters. U~equiv~ = (1/3) sum~i~[sum~j~(U~ij~ A~i~ A~j~ a*~i~ a*~j~)] A = the real space cell lengths a* = the reciprocal space cell lengths Ref: Fischer, R. X. & Tillmanns, E. (1988). Acta Cryst. C44, 775-776. The estimated standard deviation of attribute U_iso_or_equiv in category atom_site. The Wyckoff symbol (letter) as listed in the space-group section of International Tables for Crystallography, Vol. A (1987). The [1][1] element of the anisotropic atomic displacement matrix B, which appears in the structure factor term as: T = exp{-1/4 sum~i~[sum~j~(B~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute aniso_B[1][1] in category atom_site. The [1][2] element of the anisotropic atomic displacement matrix B, which appears in the structure factor term as: T = exp{-1/4 sum~i~[sum~j~(B~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute aniso_B[1][2] in category atom_site. The [1][3] element of the anisotropic atomic displacement matrix B, which appears in the structure factor term as: T = exp{-1/4 sum~i~[sum~j~(B~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute aniso_B[1][3] in category atom_site. The [2][2] element of the anisotropic atomic displacement matrix B, which appears in the structure factor term as: T = exp{-1/4 sum~i~[sum~j~(B~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute aniso_B[2][2] in category atom_site. The [2][3] element of the anisotropic atomic displacement matrix B, which appears in the structure factor term as: T = exp{-1/4 sum~i~[sum~j~(B~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute aniso_B[2][3] in category atom_site. The [3][3] element of the anisotropic atomic displacement matrix B, which appears in the structure factor term as: T = exp{-1/4 sum~i~[sum~j~(B~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute aniso_B[3][3] in category atom_site. The [1][1] element of the standard anisotropic atomic displacement matrix U, which appears in the structure factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The estimated standard deviation of attribute aniso_U[1][1] in category atom_site. The [1][2] element of the standard anisotropic atomic displacement matrix U, which appears in the structure factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The estimated standard deviation of attribute aniso_U[1][2] in category atom_site. The [1][3] element of the standard anisotropic atomic displacement matrix U, which appears in the structure factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The estimated standard deviation of attribute aniso_U[1][3] in category atom_site. The [2][2] element of the standard anisotropic atomic displacement matrix U, which appears in the structure factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The estimated standard deviation of attribute aniso_U[2][2] in category atom_site. The [2][3] element of the standard anisotropic atomic displacement matrix U, which appears in the structure factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The estimated standard deviation of attribute aniso_U[2][3] in category atom_site. The [3][3] element of the standard anisotropic atomic displacement matrix U, which appears in the structure factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The estimated standard deviation of attribute aniso_U[3][3] in category atom_site. Ratio of the maximum to minimum principal axes of displacement (thermal) ellipsoids. The number of hydrogen atoms attached to the atom at this site excluding any H atoms for which coordinates (measured or calculated) are given. water oxygen 2 hydroxyl oxygen 1 ammonium nitrogen 4 An alternative identifier for attribute label_asym_id in category atom_site that may be provided by an author in order to match the identification used in the publication that describes the structure. An alternative identifier for attribute label_atom_id in category atom_site that may be provided by an author in order to match the identification used in the publication that describes the structure. An alternative identifier for attribute label_comp_id in category atom_site that may be provided by an author in order to match the identification used in the publication that describes the structure. An alternative identifier for attribute label_seq_id in category atom_site that may be provided by an author in order to match the identification used in the publication that describes the structure. Note that this is not necessarily a number, that the values do not have to be positive, and that the value does not have to correspond to the value of attribute label_seq_id in category atom_site. The value of attribute label_seq_id in category atom_site is required to be a sequential list of positive integers. The author may assign values to attribute auth_seq_id in category atom_site in any desired way. For instance, the values may be used to relate this structure to a numbering scheme in a homologous structure, including sequence gaps or insertion codes. Alternatively, a scheme may be used for a truncated polymer that maintains the numbering scheme of the full length polymer. In all cases, the scheme used here must match the scheme used in the publication that describes the structure. The attribute id in category atom_site of the atom site to which the 'geometry- calculated' atom site is attached. A standard code to signal if the site data have been determined from the intensities or calculated from the geometry of surrounding sites, or have been assigned dummy coordinates. The abbreviation 'c' may be used in place of 'calc'. This data item is a pointer to attribute number in category chemical_conn_atom in the CHEMICAL_CONN_ATOM category. A description of the constraints applied to parameters at this site during refinement. See also attribute refinement_flags in category atom_site and attribute ls_number_constraints in category refine. pop=1.0-pop(Zn3) A description of special aspects of this site. See also attribute refinement_flags in category atom_site. Ag/Si disordered A code which identifies a cluster of atoms that show long-range positional disorder but are locally ordered. Within each such cluster of atoms, attribute disorder_group in category atom_site is used to identify the sites that are simultaneously occupied. This field is only needed if there is more than one cluster of disordered atoms showing independent local order. *** This data item would not in general be used in a macromolecular data block. *** A code that identifies a group of positionally disordered atom sites that are locally simultaneously occupied. Atoms that are positionally disordered over two or more sites (e.g. the H atoms of a methyl group that exists in two orientations) can be assigned to two or more groups. Sites belonging to the same group are simultaneously occupied, but those belonging to different groups are not. A minus prefix (e.g. "-1") is used to indicate sites disordered about a special position. *** This data item would not in general be used in a macromolecular data block. *** The value of attribute footnote_id in category atom_site must match an id specified by attribute id in category atom_sites_footnote in the ATOM_SITES_FOOTNOTE list. The x coordinate of the atom site position specified as a fraction of attribute length_a in category cell. The estimated standard deviation of attribute fract_x in category atom_site. The y coordinate of the atom site position specified as a fraction of attribute length_b in category cell. The estimated standard deviation of attribute fract_y in category atom_site. The z coordinate of the atom site position specified as a fraction of attribute length_c in category cell. The estimated standard deviation of attribute fract_z in category atom_site. The group of atoms to which the atom site belongs. This data item is provided for compatibility with the original Protein Data Bank format, and only for that purpose. A component of the macromolecular identifier for this atom site. For further details, see the definition of the ATOM_SITE_ALT category. This data item is a pointer to attribute id in category atom_sites_alt in the ATOM_SITES_ALT category. A component of the macromolecular identifier for this atom site. For further details, see the definition of the STRUCT_ASYM category. This data item is a pointer to attribute id in category struct_asym in the STRUCT_ASYM category. A component of the macromolecular identifier for this atom site. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. A component of the macromolecular identifier for this atom site. This data item is a pointer to attribute id in category chem_comp in the CHEM_COMP category. This data item is a pointer to attribute id in category entity in the ENTITY category. This data item is a pointer to attribute num in category entity_poly_seq in the ENTITY_POLY_SEQ category. PDB atom name. PDB residue name. PDB residue number. PDB strand id. The ATOM group code used by the NDB. Author's alternate location identifier Author's strand id. Author's atom name. Author's residue name. Author's sequence identifier. The ATOM group code used by the NDB. Placeholder for PDB insertion code. Sequential residue number used by NDB. The model number for a multi-model structure. Will identify with a 'Y' that this strand got generated. The fraction of the atom type present at this site. The sum of the occupancies of all the atom types at this site may not significantly exceed 1.0 unless it is a dummy site. The estimated standard deviation of attribute occupancy in category atom_site. The net integer charge assigned to this atom. This is the formal charge assignment normally found in chemical diagrams. for an ammonium nitrogen 1 for a chloride ion -1 The NCS domain to which the atom position is assigned. The NCS group is defined in category struct_ncs_dom. This item is a reference to attribute id in category struct_ncs_dom. The TLS group to which the atom position is assigned. The TLS group is defined in category pdbx_refine_tls_group. This item is a reference to attribute id in category pdbx_refine_tls_group. A concatenated series of single-letter codes which indicate the refinement restraints or constraints applied to this site. A description of restraints applied to specific parameters at this site during refinement. See also attribute refinement_flags in category atom_site and attribute ls_number_restraints in category refine. restrained to planar ring The multiplicity of a site due to the space-group symmetry as is given in International Tables for Crystallography, Vol. A (1987). A standard code used to describe the type of atomic displacement parameters used for the site. This data item is a pointer to attribute symbol in category atom_type in the ATOM_TYPE category. The value of attribute id in category atom_site must uniquely identify a record in the ATOM_SITE list. Note that this item need not be a number; it can be any unique identifier. This data item was introduced to facilitate compatibility between small molecule and macromolecular files. In the small molecule files, _atom_site_label is the identifier for the atom. In the macromolecular files, the atom identifier is the aggregate of _atom_site.label_alt_id, _atom_site.label_asym_id, _atom_site.label_atom_id, _atom_site.label_comp_id and attribute label_seq_id in category atom_site. For the two types of files to be compatible, a formal identifier for the category had to be introduced that was independent of the different modes of identifying atoms. For compatibility with older files, _atom_site_label is aliased to attribute id in category atom_site. 5 C12 Ca3g28 Fe3+17 H*251 boron2a C_a_phe_83_a_0 Zn_Zn_301_A_0 Data items in the ATOM_SITE_ANISOTROP category record details about temperature or thermal displacement factors, if those data items are contained in a separate list from the ATOM_SITE list. If the ATOM_SITE_ANISOTROP category is used for storing these data, the corresponding ATOM_SITE data items are not used. Example 1 - based on NDB structure BDL005 of Holbrook, Dickerson & Kim [(1985). Acta Cryst. B41, 255-262]. <RCSB:atom_site_anisotropCategory> <RCSB:atom_site_anisotrop id="1"> <RCSB:U11>8642.</RCSB:U11> <RCSB:U12>4866.</RCSB:U12> <RCSB:U13>7299.</RCSB:U13> <RCSB:U22>-342.</RCSB:U22> <RCSB:U23>-258.</RCSB:U23> <RCSB:U33>-1427.</RCSB:U33> <RCSB:type_symbol>O</RCSB:type_symbol> </RCSB:atom_site_anisotrop> <RCSB:atom_site_anisotrop id="2"> <RCSB:U11>5174.</RCSB:U11> <RCSB:U12>4871.</RCSB:U12> <RCSB:U13>6243.</RCSB:U13> <RCSB:U22>-1885.</RCSB:U22> <RCSB:U23>-2051.</RCSB:U23> <RCSB:U33>-1377.</RCSB:U33> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site_anisotrop> <RCSB:atom_site_anisotrop id="3"> <RCSB:U11>6202.</RCSB:U11> <RCSB:U12>5020.</RCSB:U12> <RCSB:U13>4395.</RCSB:U13> <RCSB:U22>-1130.</RCSB:U22> <RCSB:U23>-556.</RCSB:U23> <RCSB:U33>-632.</RCSB:U33> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site_anisotrop> <RCSB:atom_site_anisotrop id="4"> <RCSB:U11>4224.</RCSB:U11> <RCSB:U12>4700.</RCSB:U12> <RCSB:U13>5046.</RCSB:U13> <RCSB:U22>1105.</RCSB:U22> <RCSB:U23>-161.</RCSB:U23> <RCSB:U33>345.</RCSB:U33> <RCSB:type_symbol>O</RCSB:type_symbol> </RCSB:atom_site_anisotrop> <RCSB:atom_site_anisotrop id="5"> <RCSB:U11>8684.</RCSB:U11> <RCSB:U12>4688.</RCSB:U12> <RCSB:U13>4171.</RCSB:U13> <RCSB:U22>-1850.</RCSB:U22> <RCSB:U23>-433.</RCSB:U23> <RCSB:U33>-292.</RCSB:U33> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site_anisotrop> <RCSB:atom_site_anisotrop id="6"> <RCSB:U11>11226.</RCSB:U11> <RCSB:U12>5255.</RCSB:U12> <RCSB:U13>3532.</RCSB:U13> <RCSB:U22>-341.</RCSB:U22> <RCSB:U23>2685.</RCSB:U23> <RCSB:U33>1328.</RCSB:U33> <RCSB:type_symbol>O</RCSB:type_symbol> </RCSB:atom_site_anisotrop> <RCSB:atom_site_anisotrop id="7"> <RCSB:U11>10214.</RCSB:U11> <RCSB:U12>2428.</RCSB:U12> <RCSB:U13>5614.</RCSB:U13> <RCSB:U22>-2610.</RCSB:U22> <RCSB:U23>-1940.</RCSB:U23> <RCSB:U33>902.</RCSB:U33> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site_anisotrop> <RCSB:atom_site_anisotrop id="8"> <RCSB:U11>4590.</RCSB:U11> <RCSB:U12>3488.</RCSB:U12> <RCSB:U13>5827.</RCSB:U13> <RCSB:U22>751.</RCSB:U22> <RCSB:U23>-770.</RCSB:U23> <RCSB:U33>986.</RCSB:U33> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:atom_site_anisotrop> <RCSB:atom_site_anisotrop id="9"> <RCSB:U11>5014.</RCSB:U11> <RCSB:U12>4434.</RCSB:U12> <RCSB:U13>3447.</RCSB:U13> <RCSB:U22>-17.</RCSB:U22> <RCSB:U23>-1593.</RCSB:U23> <RCSB:U33>539.</RCSB:U33> <RCSB:type_symbol>N</RCSB:type_symbol> </RCSB:atom_site_anisotrop> </RCSB:atom_site_anisotropCategory> The [1][1] element of the anisotropic atomic displacement matrix B, which appears in the structure factor term as: T = exp{-1/4 sum~i~[sum~j~(B~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute B[1][1] in category atom_site_anisotrop. The [1][2] element of the anisotropic atomic displacement matrix B, which appears in the structure factor term as: T = exp{-1/4 sum~i~[sum~j~(B~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute B[1][2] in category atom_site_anisotrop. The [1][3] element of the anisotropic atomic displacement matrix B, which appears in the structure factor term as: T = exp{-1/4 sum~i~[sum~j~(B~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute B[1][3] in category atom_site_anisotrop. The [2][2] element of the anisotropic atomic displacement matrix B, which appears in the structure factor term as: T = exp{-1/4 sum~i~[sum~j~(B~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute B[2][2] in category atom_site_anisotrop. The [2][3] element of the anisotropic atomic displacement matrix B, which appears in the structure factor term as: T = exp{-1/4 sum~i~[sum~j~(B~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute B[2][3] in category atom_site_anisotrop. The [3][3] element of the anisotropic atomic displacement matrix B, which appears in the structure factor term as: T = exp{-1/4 sum~i~[sum~j~(B~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The estimated standard deviation of attribute B[3][3] in category atom_site_anisotrop. The [1][1] element of the standard anisotropic atomic displacement matrix U, which appears in the structure factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The estimated standard deviation of attribute U[1][1] in category atom_site_anisotrop. The [1][2] element of the standard anisotropic atomic displacement matrix U, which appears in the structure factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The estimated standard deviation of attribute U[1][2] in category atom_site_anisotrop. The [1][3] element of the standard anisotropic atomic displacement matrix U, which appears in the structure factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The estimated standard deviation of attribute U[1][3] in category atom_site_anisotrop. The [2][2] element of the standard anisotropic atomic displacement matrix U, which appears in the structure factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The estimated standard deviation of attribute U[2][2] in category atom_site_anisotrop. The [2][3] element of the standard anisotropic atomic displacement matrix U, which appears in the structure factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The estimated standard deviation of attribute U[2][3] in category atom_site_anisotrop. The [3][3] element of the standard anisotropic atomic displacement matrix U, which appears in the structure factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The estimated standard deviation of attribute U[3][3] in category atom_site_anisotrop. PDB atom name. PDB residue name. PDB residue number. PDB strand id. Author's strand id. Author's atom name. Author's residue name. NDB sequence ID. NDB ALT ID. NDB ASYM ID. NDB ATOM ID NDB COMP ID NDB INSERTION CODE Sequential residue number used by NDB. Will identify with a 'Y' that this strand got generated. Ratio of the maximum to minimum principal axes of displacement (thermal) ellipsoids. This data item is a pointer to attribute symbol in category atom_type in the ATOM_TYPE category. This data item is a pointer to attribute id in category atom_site in the ATOM_SITE category. Data items in the ATOM_SITES category record details about the crystallographic cell and cell transformations, which are common to all atom sites. Example 1 - based on PDB entry 5HVP and/or laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:atom_sitesCategory> <RCSB:atom_sites entry_id="5HVP"> <RCSB:Cartn_transf_matrix11>58.39</RCSB:Cartn_transf_matrix11> <RCSB:Cartn_transf_matrix12>0.00</RCSB:Cartn_transf_matrix12> <RCSB:Cartn_transf_matrix13>0.00</RCSB:Cartn_transf_matrix13> <RCSB:Cartn_transf_matrix21>0.00</RCSB:Cartn_transf_matrix21> <RCSB:Cartn_transf_matrix22>86.70</RCSB:Cartn_transf_matrix22> <RCSB:Cartn_transf_matrix23>0.00</RCSB:Cartn_transf_matrix23> <RCSB:Cartn_transf_matrix31>0.00</RCSB:Cartn_transf_matrix31> <RCSB:Cartn_transf_matrix32>0.00</RCSB:Cartn_transf_matrix32> <RCSB:Cartn_transf_matrix33>46.27</RCSB:Cartn_transf_matrix33> <RCSB:Cartn_transf_vector1>0.00</RCSB:Cartn_transf_vector1> <RCSB:Cartn_transf_vector2>0.00</RCSB:Cartn_transf_vector2> <RCSB:Cartn_transf_vector3>0.00</RCSB:Cartn_transf_vector3> <RCSB:Cartn_transform_axes>c along z, astar along x, b along y</RCSB:Cartn_transform_axes> </RCSB:atom_sites> </RCSB:atom_sitesCategory> The [1][1] element of the 3x3 matrix used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute Cartn_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The [1][2] element of the 3x3 matrix used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute Cartn_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The [1][3] element of the 3x3 matrix used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute Cartn_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The [2][1] element of the 3x3 matrix used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute Cartn_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The [2][2] element of the 3x3 matrix used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute Cartn_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The [2][3] element of the 3x3 matrix used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute Cartn_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The [3][1] element of the 3x3 matrix used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute Cartn_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The [3][2] element of the 3x3 matrix used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute Cartn_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The [3][3] element of the 3x3 matrix used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute Cartn_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The [1] element of the 3 element vector used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The rotation matrix is defined in attribute Cartn_transf_matrix[][]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The [2] element of the 3 element vector used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The rotation matrix is defined in attribute Cartn_transf_matrix[][]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The [3] element of the 3 element vector used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The rotation matrix is defined in attribute Cartn_transf_matrix[][]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| A description of the relative alignment of the crystal cell axes to the Cartesian orthogonal axes as applied in the transformation matrix attribute Cartn_transf_matrix in category atom_sites. a parallel to x; b in the plane of y & z The [1][1] element of the 3x3 matrix used to transform Cartesian coordinates in the ATOM_SITE category to fractional coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute fract_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~fractional~ = |21 22 23| |y|~Cartesian~ + |2| |z'| |31 32 33| |z| |3| The [1][2] element of the 3x3 matrix used to transform Cartesian coordinates in the ATOM_SITE category to fractional coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute fract_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~fractional~ = |21 22 23| |y|~Cartesian~ + |2| |z'| |31 32 33| |z| |3| The [1][3] element of the 3x3 matrix used to transform Cartesian coordinates in the ATOM_SITE category to fractional coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute fract_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~fractional~ = |21 22 23| |y|~Cartesian~ + |2| |z'| |31 32 33| |z| |3| The [2][1] element of the 3x3 matrix used to transform Cartesian coordinates in the ATOM_SITE category to fractional coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute fract_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~fractional~ = |21 22 23| |y|~Cartesian~ + |2| |z'| |31 32 33| |z| |3| The [2][3] element of the 3x3 matrix used to transform Cartesian coordinates in the ATOM_SITE category to fractional coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute fract_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~fractional~ = |21 22 23| |y|~Cartesian~ + |2| |z'| |31 32 33| |z| |3| The [2][3] element of the 3x3 matrix used to transform Cartesian coordinates in the ATOM_SITE category to fractional coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute fract_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~fractional~ = |21 22 23| |y|~Cartesian~ + |2| |z'| |31 32 33| |z| |3| The [3][1] element of the 3x3 matrix used to transform Cartesian coordinates in the ATOM_SITE category to fractional coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute fract_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~fractional~ = |21 22 23| |y|~Cartesian~ + |2| |z'| |31 32 33| |z| |3| The [3][2] element of the 3x3 matrix used to transform Cartesian coordinates in the ATOM_SITE category to fractional coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute fract_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~fractional~ = |21 22 23| |y|~Cartesian~ + |2| |z'| |31 32 33| |z| |3| The [3][3] element of the 3x3 matrix used to transform Cartesian coordinates in the ATOM_SITE category to fractional coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute fract_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~fractional~ = |21 22 23| |y|~Cartesian~ + |2| |z'| |31 32 33| |z| |3| The [1] element of the 3 element vector used to transform Cartesian coordinates in the ATOM_SITE category to fractional coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x3 rotation is defined in attribute fract_transf_matrix[][]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~fractional~ = |21 22 23| |y|~Cartesian~ + |2| |z'| |31 32 33| |z| |3| The [2] element of the 3 element vector used to transform Cartesian coordinates in the ATOM_SITE category to fractional coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x3 rotation is defined in attribute fract_transf_matrix[][]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~fractional~ = |21 22 23| |y|~Cartesian~ + |2| |z'| |31 32 33| |z| |3| The [3] element of the 3 element vector used to transform Cartesian coordinates in the ATOM_SITE category to fractional coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x3 rotation is defined in attribute fract_transf_matrix[][]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~fractional~ = |21 22 23| |y|~Cartesian~ + |2| |z'| |31 32 33| |z| |3| A code which identifies the methods used to locate the initial atomic sites. The solution_hydrogens code identifies how the hydrogens were located. *** This data item would not in general be used in a macromolecular data block. *** A code which identifies the methods used to locate the initial atomic sites. The solution_primary code identifies how the first atom sites were determined. *** This data item would not in general be used in a macromolecular data block. *** A code which identifies the methods used to locate the initial atomic sites. The solution_secondary code identifies how the non-hydrogen sites not include in solution_primary were located. *** This data item would not in general be used in a macromolecular data block. *** This data item is a pointer to attribute id in category entry in the ENTRY category. Data items in the ATOM_SITES_ALT category record details about the structural ensembles that should be generated from atom sites or groups of atom sites that are modeled in alternative conformations in this data block. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:atom_sites_altCategory> <RCSB:atom_sites_alt id="1"> <RCSB:details> Atom sites with the alternative id set to 1 have been modeled in alternative conformations with respect to atom sites marked with alternative id 2. The conformations of amino acid side chains and solvent atoms with alternative id set to 1 correlate with the conformation of the inhibitor marked with alternative id 1. They have been given an occupancy of 0.58 to match the occupancy assigned to the inhibitor.</RCSB:details> </RCSB:atom_sites_alt> <RCSB:atom_sites_alt id="2"> <RCSB:details> Atom sites with the alternative id set to 2 have been modeled in alternative conformations with respect to atom sites marked with alternative id 1. The conformations of amino acid side chains and solvent atoms with alternative id set to 2 correlate with the conformation of the inhibitor marked with alternative id 2. They have been given an occupancy of 0.42 to match the occupancy assigned to the inhibitor.</RCSB:details> </RCSB:atom_sites_alt> <RCSB:atom_sites_alt id="3"> <RCSB:details> Atom sites with the alternative id set to 3 have been modeled in alternative conformations with respect to atoms marked with alternative id 4. The conformations of amino acid side chains and solvent atoms with alternative id set to 3 do not correlate with the conformation of the inhibitor. These atom sites have arbitrarily been given an occupancy of 0.50.</RCSB:details> </RCSB:atom_sites_alt> <RCSB:atom_sites_alt id="4"> <RCSB:details> Atom sites with the alternative id set to 4 have been modeled in alternative conformations with respect to atoms marked with alternative id 3. The conformations of amino acid side chains and solvent atoms with alternative id set to 4 do not correlate with the conformation of the inhibitor. These atom sites have arbitrarily been given an occupancy of 0.50.</RCSB:details> </RCSB:atom_sites_alt> </RCSB:atom_sites_altCategory> A description of special aspects of the modeling of atoms in alternative conformations. The value of attribute id in category atom_sites_alt must uniquely identify a record in the ATOM_SITES_ALT list. Note that this item need not be a number; it can be any unique identifier. orientation 1 molecule abc Data items in the ATOM_SITES_ALT_ENS category record details about the ensemble structure generated from atoms with various alternative conformation ids. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:atom_sites_alt_ensCategory> <RCSB:atom_sites_alt_ens id="Ensemble 1-A"> <RCSB:details> The inhibitor binds to the enzyme in two, roughly twofold symmetric, alternative conformations. This conformational ensemble includes the more populated conformation of the inhibitor (id=1) and the amino acid side chains and solvent structure that correlate with this inhibitor conformation. Also included are one set (id=3) of side chains with alternative conformations when the conformations are not correlated with the inhibitor conformation.</RCSB:details> </RCSB:atom_sites_alt_ens> <RCSB:atom_sites_alt_ens id="Ensemble 1-B"> <RCSB:details> The inhibitor binds to the enzyme in two, roughly twofold symmetric alternative conformations. This conformational ensemble includes the more populated conformation of the inhibitor (id=1) and the amino acid side chains and solvent structure that correlate with this inhibitor conformation. Also included are one set (id=4) of side chains with alternative conformations when the conformations are not correlated with the inhibitor conformation.</RCSB:details> </RCSB:atom_sites_alt_ens> <RCSB:atom_sites_alt_ens id="Ensemble 2-A"> <RCSB:details> The inhibitor binds to the enzyme in two, roughly twofold symmetric alternative conformations. This conformational ensemble includes the less populated conformation of the inhibitor (id=2) and the amino acid side chains and solvent structure that correlate with this inhibitor conformation. Also included are one set (id=3) of side chains with alternative conformations when the conformations are not correlated with the inhibitor conformation.</RCSB:details> </RCSB:atom_sites_alt_ens> <RCSB:atom_sites_alt_ens id="Ensemble 2-B"> <RCSB:details> The inhibitor binds to the enzyme in two, roughly twofold symmetric alternative conformations. This conformational ensemble includes the less populated conformation of the inhibitor (id=2) and the amino acid side chains and solvent structure that correlate with this inhibitor conformation. Also included are one set (id=4) of side chains with alternative conformations when the conformations are not correlated with the inhibitor conformation.</RCSB:details> </RCSB:atom_sites_alt_ens> </RCSB:atom_sites_alt_ensCategory> A description of special aspects of the ensemble structure generated from atoms with various alternative ids. The value of attribute id in category atom_sites_alt_ens must uniquely identify a record in the ATOM_SITES_ALT_ENS list. Note that this item need not be a number; it can be any unique identifier. Data items in the ATOM_SITES_ALT_GEN category record details about the interpretation of multiple conformations in the structure. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:atom_sites_alt_genCategory> <RCSB:atom_sites_alt_gen alt_id="1" ens_id="Ensemble 1-A"></RCSB:atom_sites_alt_gen> <RCSB:atom_sites_alt_gen alt_id="3" ens_id="Ensemble 1-A"></RCSB:atom_sites_alt_gen> <RCSB:atom_sites_alt_gen alt_id="1" ens_id="Ensemble 1-B"></RCSB:atom_sites_alt_gen> <RCSB:atom_sites_alt_gen alt_id="4" ens_id="Ensemble 1-B"></RCSB:atom_sites_alt_gen> <RCSB:atom_sites_alt_gen alt_id="2" ens_id="Ensemble 2-A"></RCSB:atom_sites_alt_gen> <RCSB:atom_sites_alt_gen alt_id="3" ens_id="Ensemble 2-A"></RCSB:atom_sites_alt_gen> <RCSB:atom_sites_alt_gen alt_id="2" ens_id="Ensemble 2-B"></RCSB:atom_sites_alt_gen> <RCSB:atom_sites_alt_gen alt_id="4" ens_id="Ensemble 2-B"></RCSB:atom_sites_alt_gen> </RCSB:atom_sites_alt_genCategory> This data item is a pointer to attribute id in category atom_sites_alt in the ATOM_SITES_ALT category. This data item is a pointer to attribute id in category atom_sites_alt_ens in the ATOM_SITES_ALT_ENS category. Data items in the ATOM_SITES_FOOTNOTE category record detailed comments about an atom site or group of atom sites. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:atom_sites_footnoteCategory> <RCSB:atom_sites_footnote id="1"> <RCSB:text> The inhibitor binds to the enzyme in two alternative orientations. The two orientations have been assigned alternative ids *1* and *2*.</RCSB:text> </RCSB:atom_sites_footnote> <RCSB:atom_sites_footnote id="2"> <RCSB:text> Side chains of these residues adopt alternative orientations that correlate with the alternative orientations of the inhibitor. Side chains with alternative id *1* and occupancy 0.58 correlate with inhibitor orientation *1*. Side chains with alternative id *2* and occupancy 0.42 correlate with inhibitor orientation *2*.</RCSB:text> </RCSB:atom_sites_footnote> <RCSB:atom_sites_footnote id="3"> <RCSB:text> The positions of these water molecules correlate with the alternative orientations of the inhibitor. Water molecules with alternative id *1* and occupancy 0.58 correlate with inhibitor orientation *1*. Water molecules with alternative id *2* and occupancy 0.42 correlate with inhibitor orientation *2*.</RCSB:text> </RCSB:atom_sites_footnote> <RCSB:atom_sites_footnote id="4"> <RCSB:text> Side chains of these residues adopt alternative orientations that do not correlate with the alternative orientation of the inhibitor. </RCSB:text> </RCSB:atom_sites_footnote> <RCSB:atom_sites_footnote id="5"> <RCSB:text> The positions of these water molecules correlate with alternative orientations of amino acid side chains that do not correlate with alternative orientations of the inhibitor.</RCSB:text> </RCSB:atom_sites_footnote> </RCSB:atom_sites_footnoteCategory> The text of the footnote. Footnotes are used to describe an atom site or group of atom sites in the ATOM_SITE list. For example, footnotes may be used to indicate atoms for which the electron density is very weak, or atoms for which static disorder has been modeled, among many other possibilities. A code that identifies the footnote. a b 1 2 Data items in the ATOM_TYPE category record details about properties of the atoms that occupy the atom sites, such as the atomic scattering factors. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:atom_typeCategory> <RCSB:atom_type symbol="C"> <RCSB:oxidation_number>0</RCSB:oxidation_number> <RCSB:scat_Cromer_Mann_a1>2.31000</RCSB:scat_Cromer_Mann_a1> <RCSB:scat_Cromer_Mann_a2>20.8439</RCSB:scat_Cromer_Mann_a2> <RCSB:scat_Cromer_Mann_a3>1.02000</RCSB:scat_Cromer_Mann_a3> <RCSB:scat_Cromer_Mann_a4>10.2075</RCSB:scat_Cromer_Mann_a4> <RCSB:scat_Cromer_Mann_b1>1.58860</RCSB:scat_Cromer_Mann_b1> <RCSB:scat_Cromer_Mann_b2>0.568700</RCSB:scat_Cromer_Mann_b2> <RCSB:scat_Cromer_Mann_b3>0.865000</RCSB:scat_Cromer_Mann_b3> <RCSB:scat_Cromer_Mann_b4>51.6512</RCSB:scat_Cromer_Mann_b4> <RCSB:scat_Cromer_Mann_c>0.21560</RCSB:scat_Cromer_Mann_c> </RCSB:atom_type> <RCSB:atom_type symbol="N"> <RCSB:oxidation_number>0</RCSB:oxidation_number> <RCSB:scat_Cromer_Mann_a1>12.2126</RCSB:scat_Cromer_Mann_a1> <RCSB:scat_Cromer_Mann_a2>0.005700</RCSB:scat_Cromer_Mann_a2> <RCSB:scat_Cromer_Mann_a3>3.13220</RCSB:scat_Cromer_Mann_a3> <RCSB:scat_Cromer_Mann_a4>9.89330</RCSB:scat_Cromer_Mann_a4> <RCSB:scat_Cromer_Mann_b1>2.01250</RCSB:scat_Cromer_Mann_b1> <RCSB:scat_Cromer_Mann_b2>28.9975</RCSB:scat_Cromer_Mann_b2> <RCSB:scat_Cromer_Mann_b3>1.16630</RCSB:scat_Cromer_Mann_b3> <RCSB:scat_Cromer_Mann_b4>0.582600</RCSB:scat_Cromer_Mann_b4> <RCSB:scat_Cromer_Mann_c>-11.529</RCSB:scat_Cromer_Mann_c> </RCSB:atom_type> <RCSB:atom_type symbol="O"> <RCSB:oxidation_number>0</RCSB:oxidation_number> <RCSB:scat_Cromer_Mann_a1>3.04850</RCSB:scat_Cromer_Mann_a1> <RCSB:scat_Cromer_Mann_a2>13.2771</RCSB:scat_Cromer_Mann_a2> <RCSB:scat_Cromer_Mann_a3>2.28680</RCSB:scat_Cromer_Mann_a3> <RCSB:scat_Cromer_Mann_a4>5.70110</RCSB:scat_Cromer_Mann_a4> <RCSB:scat_Cromer_Mann_b1>1.54630</RCSB:scat_Cromer_Mann_b1> <RCSB:scat_Cromer_Mann_b2>0.323900</RCSB:scat_Cromer_Mann_b2> <RCSB:scat_Cromer_Mann_b3>0.867000</RCSB:scat_Cromer_Mann_b3> <RCSB:scat_Cromer_Mann_b4>32.9089</RCSB:scat_Cromer_Mann_b4> <RCSB:scat_Cromer_Mann_c>0.250800</RCSB:scat_Cromer_Mann_c> </RCSB:atom_type> <RCSB:atom_type symbol="S"> <RCSB:oxidation_number>0</RCSB:oxidation_number> <RCSB:scat_Cromer_Mann_a1>6.90530</RCSB:scat_Cromer_Mann_a1> <RCSB:scat_Cromer_Mann_a2>1.46790</RCSB:scat_Cromer_Mann_a2> <RCSB:scat_Cromer_Mann_a3>5.20340</RCSB:scat_Cromer_Mann_a3> <RCSB:scat_Cromer_Mann_a4>22.2151</RCSB:scat_Cromer_Mann_a4> <RCSB:scat_Cromer_Mann_b1>1.43790</RCSB:scat_Cromer_Mann_b1> <RCSB:scat_Cromer_Mann_b2>0.253600</RCSB:scat_Cromer_Mann_b2> <RCSB:scat_Cromer_Mann_b3>1.58630</RCSB:scat_Cromer_Mann_b3> <RCSB:scat_Cromer_Mann_b4>56.1720</RCSB:scat_Cromer_Mann_b4> <RCSB:scat_Cromer_Mann_c>0.866900</RCSB:scat_Cromer_Mann_c> </RCSB:atom_type> <RCSB:atom_type symbol="CL"> <RCSB:oxidation_number>-1</RCSB:oxidation_number> <RCSB:scat_Cromer_Mann_a1>18.2915</RCSB:scat_Cromer_Mann_a1> <RCSB:scat_Cromer_Mann_a2>0.006600</RCSB:scat_Cromer_Mann_a2> <RCSB:scat_Cromer_Mann_a3>7.20840</RCSB:scat_Cromer_Mann_a3> <RCSB:scat_Cromer_Mann_a4>1.17170</RCSB:scat_Cromer_Mann_a4> <RCSB:scat_Cromer_Mann_b1>6.53370</RCSB:scat_Cromer_Mann_b1> <RCSB:scat_Cromer_Mann_b2>19.5424</RCSB:scat_Cromer_Mann_b2> <RCSB:scat_Cromer_Mann_b3>2.33860</RCSB:scat_Cromer_Mann_b3> <RCSB:scat_Cromer_Mann_b4>60.4486</RCSB:scat_Cromer_Mann_b4> <RCSB:scat_Cromer_Mann_c>-16.378</RCSB:scat_Cromer_Mann_c> </RCSB:atom_type> </RCSB:atom_typeCategory> Example 2 - based on data set TOZ of Willis, Beckwith & Tozer [(1991). Acta Cryst. C47, 2276-2277]. <RCSB:atom_typeCategory> <RCSB:atom_type symbol="C"> <RCSB:number_in_cell>72</RCSB:number_in_cell> <RCSB:oxidation_number>0</RCSB:oxidation_number> <RCSB:scat_dispersion_imag>.009</RCSB:scat_dispersion_imag> <RCSB:scat_dispersion_real>.017</RCSB:scat_dispersion_real> <RCSB:scat_source>International_Tables_Vol_IV_Table_2.2B</RCSB:scat_source> </RCSB:atom_type> <RCSB:atom_type symbol="H"> <RCSB:number_in_cell>100</RCSB:number_in_cell> <RCSB:oxidation_number>0</RCSB:oxidation_number> <RCSB:scat_dispersion_imag>0.</RCSB:scat_dispersion_imag> <RCSB:scat_dispersion_real>0.</RCSB:scat_dispersion_real> <RCSB:scat_source>International_Tables_Vol_IV_Table_2.2B</RCSB:scat_source> </RCSB:atom_type> <RCSB:atom_type symbol="O"> <RCSB:number_in_cell>12</RCSB:number_in_cell> <RCSB:oxidation_number>0</RCSB:oxidation_number> <RCSB:scat_dispersion_imag>.032</RCSB:scat_dispersion_imag> <RCSB:scat_dispersion_real>.047</RCSB:scat_dispersion_real> <RCSB:scat_source>International_Tables_Vol_IV_Table_2.2B</RCSB:scat_source> </RCSB:atom_type> <RCSB:atom_type symbol="N"> <RCSB:number_in_cell>4</RCSB:number_in_cell> <RCSB:oxidation_number>0</RCSB:oxidation_number> <RCSB:scat_dispersion_imag>.018</RCSB:scat_dispersion_imag> <RCSB:scat_dispersion_real>.029</RCSB:scat_dispersion_real> <RCSB:scat_source>International_Tables_Vol_IV_Table_2.2B</RCSB:scat_source> </RCSB:atom_type> </RCSB:atom_typeCategory> Mass percentage of this atom type derived from chemical analysis. A description of the atom(s) designated by this atom type. In most cases this is the element name and oxidation state of a single atom species. For disordered or nonstoichiometric structures it will describe a combination of atom species. deuterium 0.34Fe+0.66Ni Total number of atoms of this atom type in the unit cell. Formal oxidation state of this atom type in the structure. The effective intramolecular bonding radius in angstroms of this atom type. The effective intermolecular bonding radius in angstroms of this atom type. The a1 Cromer-Mann scattering-factor coefficient used to calculate the scattering factors for this atom type. Ref: International Tables for X-ray Crystallography, Vol. IV, (1974). Table 2.2B. or: International Tables for Crystallography, Vol. C, (1991). Tables 6.1.1.4 and 6.1.1.5. The a2 Cromer-Mann scattering-factor coefficient used to calculate the scattering factors for this atom type. Ref: International Tables for X-ray Crystallography, Vol. IV, (1974). Table 2.2B. or: International Tables for Crystallography, Vol. C, (1991). Tables 6.1.1.4 and 6.1.1.5. The a3 Cromer-Mann scattering-factor coefficient used to calculate the scattering factors for this atom type. Ref: International Tables for X-ray Crystallography, Vol. IV, (1974). Table 2.2B. or: International Tables for Crystallography, Vol. C, (1991). Tables 6.1.1.4 and 6.1.1.5. The a4 Cromer-Mann scattering-factor coefficient used to calculate the scattering factors for this atom type. Ref: International Tables for X-ray Crystallography, Vol. IV, (1974). Table 2.2B. or: International Tables for Crystallography, Vol. C, (1991). Tables 6.1.1.4 and 6.1.1.5. The b1 Cromer-Mann scattering-factor coefficient used to calculate the scattering factors for this atom type. Ref: International Tables for X-ray Crystallography, Vol. IV, (1974). Table 2.2B. or: International Tables for Crystallography, Vol. C, (1991). Tables 6.1.1.4 and 6.1.1.5. The b2 Cromer-Mann scattering-factor coefficient used to calculate the scattering factors for this atom type. Ref: International Tables for X-ray Crystallography, Vol. IV, (1974). Table 2.2B. or: International Tables for Crystallography, Vol. C, (1991). Tables 6.1.1.4 and 6.1.1.5. The b3 Cromer-Mann scattering-factor coefficient used to calculate the scattering factors for this atom type. Ref: International Tables for X-ray Crystallography, Vol. IV, (1974). Table 2.2B. or: International Tables for Crystallography, Vol. C, (1991). Tables 6.1.1.4 and 6.1.1.5. The b4 Cromer-Mann scattering-factor coefficient used to calculate the scattering factors for this atom type. Ref: International Tables for X-ray Crystallography, Vol. IV, (1974). Table 2.2B. or: International Tables for Crystallography, Vol. C, (1991). Tables 6.1.1.4 and 6.1.1.5. The c Cromer-Mann scattering-factor coefficient used to calculate the scattering factors for this atom type. Ref: International Tables for X-ray Crystallography, Vol. IV, (1974). Table 2.2B. or: International Tables for Crystallography, Vol. C, (1991). Tables 6.1.1.4 and 6.1.1.5. The imaginary component of the anomalous dispersion scattering factors, f'' (in electrons), for this atom type and the radiation identified by attribute id in category diffrn_radiation_wavelength. The real component of the anomalous dispersion scattering factors, f' (in electrons), for this atom type and the radiation identified by attribute id in category diffrn_radiation_wavelength. The bound coherent scattering length in femtometres for the atom type at the isotopic composition used for the diffraction experiment. Reference to source of scattering factors used for this atom type. International Tables Vol IV Table 2.4.6B A table of scattering factors as a function of sin theta over lambda. This table should be well commented to indicate the items present. Regularly formatted lists are strongly recommended. The code used to identify the atom specie(s) representing this atom type. Normally this code is the element symbol. The code may be composed of any character except an underline with the additional proviso that digits designate an oxidation state and must be followed by a + or - character. C Cu2+ H(SDS) dummy FeNi Data items in the AUDIT category record details about the creation and subsequent updating of the data block. Note that these items apply only to the creation and updating of the data block, and should not be confused with the data items (in the JOURNAL category) that describe the time course of publication of the material in the data block. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:auditCategory> <RCSB:audit revision_id="1"> <RCSB:creation_date>1992-12-08</RCSB:creation_date> <RCSB:creation_method> Created by hand from PDB entry 5HVP, from the J. Biol. Chem. paper describing this structure and from laboratory records</RCSB:creation_method> <RCSB:update_record> 1992-12-09 adjusted to reflect comments from Brian McKeever 1992-12-10 adjusted to reflect comments from Helen Berman 1992-12-12 adjusted to reflect comments from Keith Watenpaugh</RCSB:update_record> </RCSB:audit> </RCSB:auditCategory> Example 2 - based on data set TOZ of Willis, Beckwith & Tozer [(1991). Acta Cryst. C47, 2276-2277]. <RCSB:auditCategory> <RCSB:audit> <RCSB:creation_date>1991-03-20</RCSB:creation_date> <RCSB:creation_method>from_xtal_archive_file_using_CIFIO</RCSB:creation_method> <RCSB:update_record> 1991-04-09 text and data added by Tony Willis. 1991-04-15 rec&apos;d by co-editor with diagram as manuscript HL7. 1991-04-17 adjustments based on first referees report. 1991-04-18 adjustments based on second referees report.</RCSB:update_record> </RCSB:audit> </RCSB:auditCategory> A date that the data block was created. The date format is yyyy-mm-dd. 1990-07-12 A description of how data were entered into the data block. spawned by the program QBEE A record of any changes to the data block. The update format is a date (yyyy-mm-dd) followed by a description of the changes. The latest update entry is added to the bottom of this record. 1990-07-15 Updated by the Co-editor The value of attribute revision_id in category audit must uniquely identify a record in the AUDIT list. rev1 Data items in the AUDIT_AUTHOR category record details about the author(s) of the data block. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:audit_authorCategory> <RCSB:audit_author pdbx_ordinal="1"> <RCSB:address> Department of Biophysical Chemistry Merck Research Laboratories P. O. Box 2000, Ry80M203 Rahway, New Jersey 07065 USA</RCSB:address> <RCSB:name>Fitzgerald, Paula M.D.</RCSB:name> </RCSB:audit_author> <RCSB:audit_author pdbx_ordinal="2"> <RCSB:address> Department of Biophysical Chemistry Merck Research Laboratories P. O. Box 2000, Ry80M203 Rahway, New Jersey 07065 USA</RCSB:address> <RCSB:name>McKeever, Brian M.</RCSB:name> </RCSB:audit_author> <RCSB:audit_author pdbx_ordinal="3"> <RCSB:address> Department of Biophysical Chemistry Merck Research Laboratories P. O. Box 2000, Ry80M203 Rahway, New Jersey 07065 USA</RCSB:address> <RCSB:name>Van Middlesworth, J.F.</RCSB:name> </RCSB:audit_author> <RCSB:audit_author pdbx_ordinal="4"> <RCSB:address> Department of Biophysical Chemistry Merck Research Laboratories P. O. Box 2000, Ry80M203 Rahway, New Jersey 07065 USA</RCSB:address> <RCSB:name>Springer, James P.</RCSB:name> </RCSB:audit_author> </RCSB:audit_authorCategory> The address of an author of this data block. If there are multiple authors, attribute address in category audit_author is looped with attribute name in category audit_author. Department Institute Street City and postcode COUNTRY The name of an author of this data block. If there are multiple authors, _audit_author.name is looped with _audit_author.address. The family name(s), followed by a comma and including any dynastic compoents, precedes the first name(s) or initial(s). Bleary, Percival R. O'Neil, F.K. Van den Bossche, G. Yang, D.-L. Simonov, Yu.A This data item defines the order of the author's name in the list of audit authors. 1 2 3 Data items in the AUDIT_CONFORM category describe the dictionary versions against which the data names appearing in the current data block are conformant. Example 1 - Any file conforming to the current CIF core dictionary. <RCSB:audit_conformCategory> <RCSB:audit_conform dict_name="cif_core.dic" dict_version="2.0"> <RCSB:dict_location>ftp://ftp.iucr.ac.uk/pub/cifdic.c96</RCSB:dict_location> </RCSB:audit_conform> </RCSB:audit_conformCategory> A file name or uniform resource locator (URL) where the conformant dictionary resides. The string identifying the highest-level dictionary defining datanames used in this file. The version number of the conformant dictionary. Data items in the AUDIT_CONTACT_AUTHOR category record details about the name and address of the author to be contacted concerning the contents of this data block. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:audit_contact_authorCategory> <RCSB:audit_contact_author name="Fitzgerald, Paula M.D."> <RCSB:address> Department of Biophysical Chemistry Merck Research Laboratories P. O. Box 2000, Ry80M203 Rahway, New Jersey 07065 USA</RCSB:address> <RCSB:email>paula_fitzgerald@merck.com</RCSB:email> <RCSB:fax>908 594 6645</RCSB:fax> <RCSB:phone>908 594 5510</RCSB:phone> </RCSB:audit_contact_author> </RCSB:audit_contact_authorCategory> The mailing address of the author of the data block to whom correspondence should be addressed. Department Institute Street City and postcode COUNTRY The electronic mail address of the author of the data block to whom correspondence should be addressed, in a form recognisable to international networks. name@host.domain.country bm@iucr.ac.uk The facsimile telephone number of the author of the data block to whom correspondence should be addressed. The recommended style includes the international dialing prefix, the area code in parentheses, followed by the local number with no spaces. The earlier convention of including the international dialing prefixes in parentheses is no longer recommended. 12(34)9477334 12()349477334 The telephone number of the author of the data block to whom correspondence should be addressed. The recommended style includes the international dialing prefix, the area code in parentheses, followed by the local number and any extension number prefixed by 'x', with no spaces. The earlier convention of including the international dialing prefixes in parentheses is no longer recommended. 12(34)9477330 12()349477330 12(34)9477330x5543 The name of the author of the data block to whom correspondence should be addressed. The family name(s), followed by a comma and including any dynastic components, precedes the first name(s) or initial(s). Bleary, Percival R. O'Neil, F.K. Van den Bossche, G. Yang, D.-L. Simonov, Yu.A Data items in the REFINE_TLS category record details about TLS parameters used in structure refinement. Note that the intention is primarily to describe directly refined TLS parameters, although other methods of obtaining TLS parameters may be covered, see item attribute method in category ccp4_refine_tls The [1][1] element of the libration tensor L. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. The estimated standard deviation of attribute L[1][1] in category ccp4_refine_tls. The [1][2] element of the libration tensor L. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. The estimated standard deviation of attribute L[1][2] in category ccp4_refine_tls. The [1][3] element of the libration tensor L. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. The estimated standard deviation of attribute L[1][3] in category ccp4_refine_tls. The [2][2] element of the libration tensor L. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. The estimated standard deviation of attribute L[2][2] in category ccp4_refine_tls. The [2][3] element of the libration tensor L. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. The estimated standard deviation of attribute L[2][3] in category ccp4_refine_tls. The [3][3] element of the libration tensor L. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. The estimated standard deviation of attribute L[3][3] in category ccp4_refine_tls. The [1][1] element of the screw-rotation tensor S. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. The trace of S is indeterminate by crystallography, and should be set to zero. The estimated standard deviation of attribute S[1][1] in category ccp4_refine_tls. The [1][2] element of the screw-rotation tensor S. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. If the origin is omitted, it is assumed to be the centre of reaction of the group, in which case S must be symmetric The estimated standard deviation of attribute S[1][2] in category ccp4_refine_tls. The [1][3] element of the screw-rotation tensor S. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. If the origin is omitted, it is assumed to be the centre of reaction of the group, in which case S must be symmetric The estimated standard deviation of attribute S[1][3] in category ccp4_refine_tls. The [2][1] element of the screw-rotation tensor S. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. If the origin is omitted, it is assumed to be the centre of reaction of the group, in which case S must be symmetric The estimated standard deviation of attribute S[2][1] in category ccp4_refine_tls. The [2][2] element of the screw-rotation tensor S. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. The trace of S is indeterminate by crystallography, and should be set to zero. The estimated standard deviation of attribute S[2][2] in category ccp4_refine_tls. The [2][3] element of the screw-rotation tensor S. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. If the origin is omitted, it is assumed to be the centre of reaction of the group, in which case S must be symmetric The estimated standard deviation of attribute S[2][3] in category ccp4_refine_tls. The [3][1] element of the screw-rotation tensor S. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. If the origin is omitted, it is assumed to be the centre of reaction of the group, in which case S must be symmetric The estimated standard deviation of attribute S[3][1] in category ccp4_refine_tls. The [3][2] element of the screw-rotation tensor S. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. If the origin is omitted, it is assumed to be the centre of reaction of the group, in which case S must be symmetric The estimated standard deviation of attribute S[3][2] in category ccp4_refine_tls. The [3][3] element of the screw-rotation tensor S. This should be given in the same coordinate frame as the corresponding anisotropic displacement parameters. The trace of S is indeterminate by crystallography, and should be set to zero. The estimated standard deviation of attribute S[3][3] in category ccp4_refine_tls. The [1][1] element of the translation tensor T. This should be given in the same coordinate frame and units as the corresponding anisotropic displacement parameters. The estimated standard deviation of attribute T[1][1] in category ccp4_refine_tls. The [1][2] element of the translation tensor T. This should be given in the same coordinate frame and units as the corresponding anisotropic displacement parameters. The estimated standard deviation of attribute T[1][2] in category ccp4_refine_tls. The [1][3] element of the translation tensor T. This should be given in the same coordinate frame and units as the corresponding anisotropic displacement parameters. The estimated standard deviation of attribute T[1][3] in category ccp4_refine_tls. The [2][2] element of the translation tensor T. This should be given in the same coordinate frame and units as the corresponding anisotropic displacement parameters. The estimated standard deviation of attribute T[2][2] in category ccp4_refine_tls. The [2][3] element of the translation tensor T. This should be given in the same coordinate frame and units as the corresponding anisotropic displacement parameters. The estimated standard deviation of attribute T[2][3] in category ccp4_refine_tls. The [3][3] element of the translation tensor T. This should be given in the same coordinate frame and units as the corresponding anisotropic displacement parameters. The estimated standard deviation of attribute T[3][3] in category ccp4_refine_tls. A description of the TLS group, such as a domain name or a chemical group name. Chain A catalytic domain Chain A Tyr 56 side chain The method by which the TLS parameters were obtained. The x coordinate in angstroms of the origin to which the TLS parameters are referred, specified according to a set of orthogonal Cartesian axes related to the cell axes as given in attribute Cartn_transform_axes. in category atom_sites If the origin is omitted, it is assumed to be the centre of reaction of the group, in which case S must be symmetric The y coordinate in angstroms of the origin to which the TLS parameters are referred, specified according to a set of orthogonal Cartesian axes related to the cell axes as given in attribute Cartn_transform_axes. in category atom_sites If the origin is omitted, it is assumed to be the centre of reaction of the group, in which case S must be symmetric The z coordinate in angstroms of the origin to which the TLS parameters are referred, specified according to a set of orthogonal Cartesian axes related to the cell axes as given in attribute Cartn_transform_axes. in category atom_sites If the origin is omitted, it is assumed to be the centre of reaction of the group, in which case S must be symmetric This data item uniquely identifies a refinement within an entry. attribute pdbx_refine_id in category ccp4_refine_tls can be used to distinguish the results of joint refinements. The value of attribute id in category ccp4_refine_tls must uniquely identify a record in the CCP4_REFINE_TLS list. Note that this item need not be a number; it can be any unique identifier. 1 A Data items in the CCP4_REFINE_TLS_GROUP category record details about a fragment of a TLS group. Properties of the TLS group are recorded in CCP4_REFINE_TLS A component of the identifier for the residue at which the TLS fragment range begins. This data item is a pointer to attribute auth_asym_id in category atom_site in the ATOM_SITE category. O 2B3 A component of the identifier for the residue at which the TLS fragment range begins. This data item is a pointer to attribute auth_seq_id in category atom_site in the ATOM_SITE category. 1 303 5A A component of the identifier for the residue at which the TLS fragment range ends. This data item is a pointer to attribute auth_asym_id in category atom_site in the ATOM_SITE category. O 2B3 A component of the identifier for the residue at which the TLS fragment range ends. This data item is a pointer to attribute auth_seq_id in category atom_site in the ATOM_SITE category. 1 5A A component of the identifier for the residue at which the TLS fragment range ends. This data item is a pointer to attribute label_asym_id in category atom_site in the ATOM_SITE category. O 2B3 A component of the identifier for the residue at which the TLS fragment range ends. This data item is a pointer to attribute label_seq_id in category atom_site in the ATOM_SITE category. 1 303 This data item uniquely identifies a refinement within an entry. attribute pdbx_refine_id in category ccp4_refine_tls_group can be used to distinguish the results of joint refinements. This data item is a pointer to attribute id in category ccp4_refine_tls in the REFINE_TLS category. A description of the subset of atoms in the specified range included in the TLS fragment. The value of attribute id in category ccp4_refine_tls_group must uniquely identify a record in the REFINE_TLS_GROUP list. Note that this item need not be a number; it can be any unique identifier. 1 A Data items in the CELL category record details about the crystallographic cell parameters. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:cellCategory> <RCSB:cell entry_id="5HVP"> <RCSB:angle_alpha>90.00</RCSB:angle_alpha> <RCSB:angle_beta>90.00</RCSB:angle_beta> <RCSB:angle_gamma>90.00</RCSB:angle_gamma> <RCSB:details> The cell parameters were refined every twenty frames during data integration. The cell lengths given are the mean of 55 such refinements; the esds given are the root mean square deviations of these 55 observations from that mean.</RCSB:details> <RCSB:length_a>58.39</RCSB:length_a> <RCSB:length_a_esd>0.05</RCSB:length_a_esd> <RCSB:length_b>86.70</RCSB:length_b> <RCSB:length_b_esd>0.12</RCSB:length_b_esd> <RCSB:length_c>46.27</RCSB:length_c> <RCSB:length_c_esd>0.06</RCSB:length_c_esd> <RCSB:volume>234237.</RCSB:volume> </RCSB:cell> </RCSB:cellCategory> Example 2 - based on data set TOZ of Willis, Beckwith & Tozer [(1991). Acta Cryst. C47, 2276-2277]. <RCSB:cellCategory> <RCSB:cell> <RCSB:angle_alpha>90.0</RCSB:angle_alpha> <RCSB:angle_beta>90.0</RCSB:angle_beta> <RCSB:angle_gamma>90.0</RCSB:angle_gamma> <RCSB:length_a>5.959</RCSB:length_a> <RCSB:length_a_esd>0.001</RCSB:length_a_esd> <RCSB:length_b>14.956</RCSB:length_b> <RCSB:length_b_esd>0.001</RCSB:length_b_esd> <RCSB:length_c>19.737</RCSB:length_c> <RCSB:length_c_esd>0.003</RCSB:length_c_esd> <RCSB:volume>1759.0</RCSB:volume> <RCSB:volume_esd>0.3</RCSB:volume_esd> </RCSB:cell> </RCSB:cellCategory> The number of the polymeric chains in a unit cell. In the case of heteropolymers, Z is the number of occurrences of the most populous chain. This data item is provided for compatibility with the original Protein Data Bank format, and only for that purpose. Unit-cell angle alpha in degrees of the reported structure. The estimated standard deviation of attribute angle_alpha in category cell. Unit-cell angle beta in degrees of the reported structure. The estimated standard deviation of attribute angle_beta in category cell. Unit-cell angle gamma in degrees of the reported structure. The estimated standard deviation of attribute angle_gamma in category cell. A description of special aspects of the cell choice, noting possible alternative settings. pseudo-orthorhombic standard setting from 45 deg rotation around c The number of the formula units in the unit cell as specified by _chemical_formula.structural, _chemical_formula.moiety or attribute sum in category chemical_formula. Unit-cell length a corresponding to the structure reported. The estimated standard deviation of attribute length_a in category cell. Unit-cell length b corresponding to the structure reported. The estimated standard deviation of attribute length_b in category cell. Unit-cell length c corresponding to the structure reported. The estimated standard deviation of attribute length_c in category cell. To further identify unique axis if necessary. E.g., P 21 with an unique C axis will have 'C' in this field. Cell volume V in angstroms cubed. V = a b c (1 - cos^2^~alpha~ - cos^2^~beta~ - cos^2^~gamma~ + 2 cos~alpha~ cos~beta~ cos~gamma~)^1/2^ a = attribute length_a in category cell b = attribute length_b in category cell c = attribute length_c in category cell alpha = attribute angle_alpha in category cell beta = attribute angle_beta in category cell gamma = attribute angle_gamma in category cell The estimated standard deviation of attribute volume in category cell. This data item is a pointer to attribute id in category entry in the ENTRY category. Data items in the CELL_MEASUREMENT category record details about the measurement of the crystallographic cell parameters. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:cell_measurementCategory> <RCSB:cell_measurement entry_id="5HVP"> <RCSB:temp>293.</RCSB:temp> <RCSB:temp_esd>3.</RCSB:temp_esd> <RCSB:theta_max>31.</RCSB:theta_max> <RCSB:theta_min>11.</RCSB:theta_min> <RCSB:wavelength>1.54</RCSB:wavelength> </RCSB:cell_measurement> </RCSB:cell_measurementCategory> Example 2 - based on data set TOZ of Willis, Beckwith & Tozer [(1991). Acta Cryst. C47, 2276-2277]. <RCSB:cell_measurementCategory> <RCSB:cell_measurement> <RCSB:reflns_used>25</RCSB:reflns_used> <RCSB:temp>293.</RCSB:temp> <RCSB:theta_max>31.</RCSB:theta_max> <RCSB:theta_min>25.</RCSB:theta_min> </RCSB:cell_measurement> </RCSB:cell_measurementCategory> The pressure in kilopascals at which the unit-cell parameters were measured (not the pressure used to synthesize the sample). The estimated standard deviation of attribute pressure in category cell_measurement. Description of the radiation used to measure the unit-cell data. See also attribute wavelength in category cell_measurement. neutron Cu K\a synchrotron The total number of reflections used to determine the unit cell. These reflections may be specified as CELL_MEASUREMENT_REFLN data items. The temperature in kelvins at which the unit-cell parameters were measured (not the temperature of synthesis). The estimated standard deviation of attribute temp in category cell_measurement. The maximum theta angle in degrees of reflections used to measure the unit cell. The minimum theta angle in degrees of reflections used to measure the unit cell. The wavelength in angstroms of the radiation used to measure the unit cell. If this is not specified, the wavelength is assumed to be that specified in the category DIFFRN_RADIATION_WAVELENGTH. This data item is a pointer to attribute id in category entry in the ENTRY category. Data items in the CELL_MEASUREMENT_REFLN category record details about the reflections used in determination of the crystallographic cell parameters. The CELL_MEASUREMENT_REFLN data items would in general be used only for diffractometer data. Example 1 - extracted from the CAD-4 listing of Rb~2~S~2~O~6~ at room temperature (not yet published). <RCSB:cell_measurement_reflnCategory> <RCSB:cell_measurement_refln index_h="-2" index_k="4" index_l="1"> <RCSB:theta>8.67</RCSB:theta> </RCSB:cell_measurement_refln> <RCSB:cell_measurement_refln index_h="0" index_k="3" index_l="2"> <RCSB:theta>9.45</RCSB:theta> </RCSB:cell_measurement_refln> <RCSB:cell_measurement_refln index_h="3" index_k="0" index_l="2"> <RCSB:theta>9.46</RCSB:theta> </RCSB:cell_measurement_refln> <RCSB:cell_measurement_refln index_h="-3" index_k="4" index_l="1"> <RCSB:theta>8.93</RCSB:theta> </RCSB:cell_measurement_refln> <RCSB:cell_measurement_refln index_h="-2" index_k="1" index_l="-2"> <RCSB:theta>7.53</RCSB:theta> </RCSB:cell_measurement_refln> <RCSB:cell_measurement_refln index_h="10" index_k="0" index_l="0"> <RCSB:theta>23.77</RCSB:theta> </RCSB:cell_measurement_refln> <RCSB:cell_measurement_refln index_h="0" index_k="10" index_l="0"> <RCSB:theta>23.78</RCSB:theta> </RCSB:cell_measurement_refln> <RCSB:cell_measurement_refln index_h="-5" index_k="4" index_l="1"> <RCSB:theta>11.14</RCSB:theta> </RCSB:cell_measurement_refln> </RCSB:cell_measurement_reflnCategory> Theta angle in degrees of a reflection used for measurement of the unit cell. Miller index h of a reflection used for measurement of the unit cell. Miller index k of a reflection used for measurement of the unit cell. Miller index l of a reflection used for measurement of the unit cell. Data items in the CHEM_COMP category give details (such as name, mass, charge, etc.) about each of the chemical components from which the relevant chemical structures can be constructed. The related categories CHEM_COMP_ATOM, CHEM_COMP_BOND, CHEM_COMP_ANGLE, etc. describe the detailed geometry of these chemical components. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:chem_compCategory> <RCSB:chem_comp id="phe"> <RCSB:model_source>1987 Protin/Prolsq Ideals file</RCSB:model_source> <RCSB:name>phenylalanine</RCSB:name> </RCSB:chem_comp> <RCSB:chem_comp id="val"> <RCSB:model_source>1987 Protin/Prolsq Ideals file</RCSB:model_source> <RCSB:name>alanine</RCSB:name> </RCSB:chem_comp> </RCSB:chem_compCategory> The formula for the chemical component. Formulae are written according to the rules: 1. Only recognised element symbols may be used. 2. Each element symbol is followed by a 'count' number. A count of '1' may be omitted. 3. A space or parenthesis must separate each element symbol and its count, but in general parentheses are not used. 4. The order of elements depends on whether or not carbon is present. If carbon is present, the order should be: C, then H, then the other elements in alphabetical order of their symbol. If carbon is not present, the elements are listed purely in alphabetic order of their symbol. This is the 'Hill' system used by Chemical Abstracts. C18 H19 N7 O8 S Formula mass in daltons of the chemical component. A description of special aspects of the generation of the coordinates for the model of the component. geometry idealized but not minimized A pointer to an 'external reference file', if the atomic description of the component is taken from such a file. The source of the coordinates for the model of the component. CSD entry ABCDEF built using Quanta/Charmm A description of the class of a non-standard monomer, if the group represents a modification of a standard monomer. iodinated base phosphorylated amino acid brominated base modified amino acid glycosylated amino acid A description of special details of a non-standard monomer. 'yes' indicates that this is a "standard" monomer, 'no' that it is "non-standard." Non-standard monomers should be further described using the attribute mon_nstd_parent, in category chem_comp _chem_comp.mon_nstd_class, and _chem_comp.mon_nstd_details data items. A name of the parent monomer of the non-standard monomer, if this group represents a modification of a standard monomer. tyrosine cytosine The identifier for the parent component of the non-standard component. This data item is a pointer to attribute id in category chem_comp in the CHEM_COMP category. The full name of the component. alanine valine adenine cytosine A type classification of this chemical component. A serial number used by PDB in the FORMUL record. 3 Formal charge for component. A synonym for the name of the component. ATP A type classification of this chemical component. Older NDB internal type code. The total number of atoms in the component. The number of non-hydrogen atoms in the component. For standard polymer components, the one-letter code for the component. If there is not a standard one-letter code for this component, or if this is a non-polymer component, the one-letter code should be given as 'X'. This code may be preceded by a '+' character to indicate that the component is a modification of a standard component. alanine or adenine A ambiguous asparagine/aspartic-acid B arginine R asparagine N aspartic-acid D cysteine or cystine or cytosine C glutamine Q glutamic-acid E ambiguous glutamine/glutamic acid Z glycine or guanine G histidine H isoleucine I leucine L lysine K methionine M phenylalanine F proline P serine S threonine or thymine T tryptophan W tyrosine Y valine V uracil U water O other X A preliminary classification used by PDB to indicate that the chemistry of this component while described as clearly as possible is still ambiguous. Software tools may not be able to process this component definition. This data item identifies the deposition site that processed this chemical component defintion. Identifies the attribute id in category chem_comp of the component that has replaced this component. q11 tvx Identifies the attribute id's in category chem_comp of the components which have been replaced by this component. Multiple id codes should be separated by commas. q11 tvx,atv The list of subcomponents contained in this component. TSM DPH HIS CHF EMR Chemical Abstract Service identifier. Internal classifier used to organize ligand dictionary (broad chemical class). HETEROCYCLIC AROMATIC COMPOUNDS Internal classifier used to organize ligand dictionary (notable chemical features). COMPOUNDS WITH THIAZOLIDINE Date component was added to database. For nonstandard components a text description of modification of the parent component. ATP Date component was last modified. NSC identifier for component. Previous chemical name used for this component if a name correction has been made. SMILES code for component. Release status of component Modification flag. For standard polymer components, the three-letter code for the component. If there is not a standard three-letter code for this component, or if this is a non-polymer component, the three-letter code should be given as 'UNK'. This code may be preceded by a '+' character to indicate that the component is a modification of a standard component. alanine ALA arginine ARG asparagine ASN aspartic-acid ASP ambiguous asparagine/aspartic-acid ASX cysteine CYS glutamine GLN glutamic-acid GLU glycine GLY ambiguous glutamine/glutamic acid GLX histidine HIS isoleucine ILE leucine LEU lysine LYS methionine MET phenylalanine PHE proline PRO serine SER threonine THR tryptophan TRP tyrosine TRY valine VAL 1-methyladenosine 1MA 5-methycytosine 5MC 2(prime)-O-methycytodine OMC 1-methyguanosine 1MG N(2)-methyguanosine 2MG N(2)-dimethyguanosine M2G 7-methyguanosine 7MG 2(prime)-O-methyguanosine 0MG diydrouridine H2U ribosylthymidine 5MU pseudouridine PSU acetic acid ACE formic acid FOR water HOH other UNK For standard polymer components, the type of the monomer. Note that monomers that will form polymers are of three types: linking monomers, monomers with some type of N-terminal (or 5') cap, and monomers with some type of C-terminal (or 3') cap. The value of attribute id in category chem_comp must uniquely identify each item in the CHEM_COMP list. For protein polymer entities, this is the three-letter code for amino acids. For nucleic acid polymer entities, this is the one-letter code for the bases. ala val A C Data items in the CHEM_COMP_ANGLE category record details about angles in a chemical component. Angles are designated by three atoms, with the second atom forming the vertex of the angle. Target values may be specified as angles in degrees, as a distance between the first and third atoms, or both. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:chem_comp_angleCategory> <RCSB:chem_comp_angle atom_id_1="N" atom_id_2="CA" atom_id_3="C" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CA" atom_id_2="C" atom_id_3="O" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CB" atom_id_2="CA" atom_id_3="C" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CB" atom_id_2="CA" atom_id_3="N" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CA" atom_id_2="CB" atom_id_3="CG" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CB" atom_id_2="CG" atom_id_3="CD1" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CB" atom_id_2="CG" atom_id_3="CD2" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CD1" atom_id_2="CG" atom_id_3="CD2" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CG" atom_id_2="CD1" atom_id_3="CE1" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CD1" atom_id_2="CE1" atom_id_3="CZ" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CE1" atom_id_2="CZ" atom_id_3="CE2" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CZ" atom_id_2="CE2" atom_id_3="CD2" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CG" atom_id_2="CD2" atom_id_3="CE2" comp_id="phe"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="N" atom_id_2="CA" atom_id_3="C" comp_id="val"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CA" atom_id_2="C" atom_id_3="O" comp_id="val"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CB" atom_id_2="CA" atom_id_3="C" comp_id="val"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CB" atom_id_2="CA" atom_id_3="N" comp_id="val"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CA" atom_id_2="CB" atom_id_3="CG1" comp_id="val"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CA" atom_id_2="CB" atom_id_3="CG2" comp_id="val"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> <RCSB:chem_comp_angle atom_id_1="CG1" atom_id_2="CB" atom_id_3="CG2" comp_id="val"> <RCSB:value_angle>xxx.xx</RCSB:value_angle> <RCSB:value_dist>x.xx</RCSB:value_dist> </RCSB:chem_comp_angle> </RCSB:chem_comp_angleCategory> The value that should be taken as the target value for the angle associated with the specified atoms, expressed in degrees. The estimated standard deviation of attribute value_angle in category chem_comp_angle. The value that should be taken as the target value for the angle associated with the specified atoms, expressed as the distance between the atoms specified by attribute atom_id_1 in category chem_comp_angle and attribute atom_id_3 in category chem_comp_angle. The estimated standard deviation of attribute value_dist_esd in category chem_comp_angle. The id of the first of the three atoms that define the angle. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. The id of the second of the three atoms that define the angle. The second atom is taken to be the apex of the angle. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. The id of the third of the three atoms that define the angle. This data item is a pointer to attribute atom_id in category chem_comp_atom in the chem_comp_atom category. This data item is a pointer to attribute id in category chem_comp in the CHEM_COMP category. Data items in the CHEM_COMP_ATOM category record details about the atoms in a chemical component. Atomic coordinates can be given for the components; specifying coordinates is an alternative to specifying the structure of the component via bonds, angles, planes, etc., in the appropriate CHEM_COMP subcategories. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:chem_comp_atomCategory> <RCSB:chem_comp_atom atom_id="N" comp_id="phe"> <RCSB:model_Cartn_x>1.20134</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>0.84658</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>0.00000</RCSB:model_Cartn_z> <RCSB:substruct_code>main</RCSB:substruct_code> <RCSB:type_symbol>N</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="CA" comp_id="phe"> <RCSB:model_Cartn_x>0.00000</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>0.00000</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>0.00000</RCSB:model_Cartn_z> <RCSB:substruct_code>main</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="C" comp_id="phe"> <RCSB:model_Cartn_x>-1.25029</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>0.88107</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>0.00000</RCSB:model_Cartn_z> <RCSB:substruct_code>main</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="O" comp_id="phe"> <RCSB:model_Cartn_x>-2.18525</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>0.66029</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>-0.78409</RCSB:model_Cartn_z> <RCSB:substruct_code>main</RCSB:substruct_code> <RCSB:type_symbol>O</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="CB" comp_id="phe"> <RCSB:model_Cartn_x>0.00662</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>-1.03603</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>1.11081</RCSB:model_Cartn_z> <RCSB:substruct_code>side</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="CG" comp_id="phe"> <RCSB:model_Cartn_x>0.03254</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>-0.49711</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>2.50951</RCSB:model_Cartn_z> <RCSB:substruct_code>side</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="CD1" comp_id="phe"> <RCSB:model_Cartn_x>-1.15813</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>-0.12084</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>3.13467</RCSB:model_Cartn_z> <RCSB:substruct_code>side</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="CE1" comp_id="phe"> <RCSB:model_Cartn_x>-1.15720</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>0.38038</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>4.42732</RCSB:model_Cartn_z> <RCSB:substruct_code>side</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="CZ" comp_id="phe"> <RCSB:model_Cartn_x>0.05385</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>0.51332</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>5.11032</RCSB:model_Cartn_z> <RCSB:substruct_code>side</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="CE2" comp_id="phe"> <RCSB:model_Cartn_x>1.26137</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>0.11613</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>4.50975</RCSB:model_Cartn_z> <RCSB:substruct_code>side</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="CD2" comp_id="phe"> <RCSB:model_Cartn_x>1.23668</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>-0.38351</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>3.20288</RCSB:model_Cartn_z> <RCSB:substruct_code>side</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="N" comp_id="val"> <RCSB:model_Cartn_x>1.20134</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>0.84658</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>0.00000</RCSB:model_Cartn_z> <RCSB:substruct_code>main</RCSB:substruct_code> <RCSB:type_symbol>N</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="CA" comp_id="val"> <RCSB:model_Cartn_x>0.00000</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>0.00000</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>0.00000</RCSB:model_Cartn_z> <RCSB:substruct_code>main</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="C" comp_id="val"> <RCSB:model_Cartn_x>-1.25029</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>0.88107</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>0.00000</RCSB:model_Cartn_z> <RCSB:substruct_code>main</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="O" comp_id="val"> <RCSB:model_Cartn_x>-2.18525</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>0.66029</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>-0.78409</RCSB:model_Cartn_z> <RCSB:substruct_code>main</RCSB:substruct_code> <RCSB:type_symbol>O</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="CB" comp_id="val"> <RCSB:model_Cartn_x>0.05260</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>-0.99339</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>1.17429</RCSB:model_Cartn_z> <RCSB:substruct_code>side</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="CG1" comp_id="val"> <RCSB:model_Cartn_x>-0.13288</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>-0.31545</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>2.52668</RCSB:model_Cartn_z> <RCSB:substruct_code>side</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> <RCSB:chem_comp_atom atom_id="CG2" comp_id="val"> <RCSB:model_Cartn_x>-0.94265</RCSB:model_Cartn_x> <RCSB:model_Cartn_y>-2.12930</RCSB:model_Cartn_y> <RCSB:model_Cartn_z>0.99811</RCSB:model_Cartn_z> <RCSB:substruct_code>side</RCSB:substruct_code> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chem_comp_atom> </RCSB:chem_comp_atomCategory> An alternative identifier for the atom. This data item would be used in cases where alternative nomenclatures exist for labeling atoms in a group. The net integer charge assigned to this atom. This is the formal charge assignment normally found in chemical diagrams. for an ammonium nitrogen 1 for a chloride ion -1 The x component of the coordinates for this atom in this component specified as orthogonal angstroms. The choice of reference axis frame for the coordinates is arbitrary. The set of coordinates input for the entity here is intended to correspond to the atomic model used to generate restraints for structure refinement, and not to atom sites in the _atom_site list. The estimated standard deviation of attribute model_Cartn_x in category chem_comp_atom. The y component of the coordinates for this atom in this component specified as orthogonal angstroms. The choice of reference axis frame for the coordinates is arbitrary. The set of coordinates input for the entity here is intended to correspond to the atomic model used to generate restraints for structure refinement, and not to atom sites in the _atom_site list. The estimated standard deviation of attribute model_Cartn_y in category chem_comp_atom. The x component of the coordinates for this atom in this component specified as orthogonal angstroms. The choice of reference axis frame for the coordinates is arbitrary. The set of coordinates input for the entity here is intended to correspond to the atomic model used to generate restraints for structure refinement, and not to atom sites in the _atom_site list. The estimated standard deviation of attribute model_Cartn_z in category chem_comp_atom. The partial charge assigned to this atom. The atom identifier in the subcomponent where a larger component has been divided subcomponents. CB CA CG The component identifier for the subcomponent where a larger component has been divided subcomponents. HIS PRO Ordinal index for the component atom list. Atom name alignment offset in PDB atom field. This data item assigns the atom to a substructure of the component, if appropriate. This data item is a pointer to attribute symbol in category atom_type in the ATOM_TYPE category. The value of attribute atom_id in category chem_comp_atom must uniquely identify each atom in each monomer in the CHEM_COMP_ATOM list. The atom identifiers need not be unique over all atoms in the data block; they need only be unique for each atom in a component. Note that this item need not be a number; it can be any unique identifier. This data item is a pointer to attribute id in category chem_comp in the CHEM_COMP category. Data items in the CHEM_COMP_BOND category record details about the bonds between atoms in a chemical component. Target values may be specified as bond orders, as a distance between the two atoms, or both. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:chem_comp_bondCategory> <RCSB:chem_comp_bond atom_id_1="N" atom_id_2="CA" comp_id="phe"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>sing</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CA" atom_id_2="C" comp_id="phe"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>sing</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="C" atom_id_2="O" comp_id="phe"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>doub</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CB" atom_id_2="CA" comp_id="phe"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>sing</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CB" atom_id_2="CG" comp_id="phe"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>sing</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CG" atom_id_2="CD1" comp_id="phe"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>arom</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CD1" atom_id_2="CE1" comp_id="phe"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>arom</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CE1" atom_id_2="CZ" comp_id="phe"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>arom</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CZ" atom_id_2="CE2" comp_id="phe"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>arom</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CE2" atom_id_2="CD2" comp_id="phe"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>arom</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CD2" atom_id_2="CG" comp_id="phe"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>arom</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="N" atom_id_2="CA" comp_id="val"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>sing</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CA" atom_id_2="C" comp_id="val"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>sing</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="C" atom_id_2="O" comp_id="val"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>doub</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CB" atom_id_2="CA" comp_id="val"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>sing</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CB" atom_id_2="CG1" comp_id="val"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>sing</RCSB:value_order> </RCSB:chem_comp_bond> <RCSB:chem_comp_bond atom_id_1="CB" atom_id_2="CG2" comp_id="val"> <RCSB:value_dist>x.xx</RCSB:value_dist> <RCSB:value_order>sing</RCSB:value_order> </RCSB:chem_comp_bond> </RCSB:chem_comp_bondCategory> Ordinal index for the component bond list. The value that should be taken as the target for the chemical bond associated with the specified atoms, expressed as a distance. The estimated standard deviation of attribute value_dist in category chem_comp_bond. The value that should be taken as the target for the chemical bond associated with the specified atoms, expressed as a bond order. The id of the first of the two atoms that define the bond. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. The id of the second of the two atoms that define the bond. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. This data item is a pointer to attribute id in category chem_comp in the CHEM_COMP category. Data items in the CHEM_COMP_CHIR category provide detail about the chiral centers in a chemical component. The atoms bonded to the chiral atom are specified in the CHEM_COMP_CHIR_ATOM category. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:chem_comp_chirCategory> <RCSB:chem_comp_chir comp_id="phe" id="phe1"> <RCSB:atom_id>CA</RCSB:atom_id> </RCSB:chem_comp_chir> <RCSB:chem_comp_chir comp_id="val" id="val1"> <RCSB:atom_id>CA</RCSB:atom_id> </RCSB:chem_comp_chir> </RCSB:chem_comp_chirCategory> The chiral configuration of the atom that is a chiral center. The id of the atom that is a chiral center. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. The total number of atoms bonded to the atom specified by attribute atom_id in category chem_comp_chir. The number of non-hydrogen atoms bonded to the atom specified by attribute atom_id in category chem_comp_chir. A flag to indicate whether a chiral volume should match the standard value in both magnitude and sign, or in magnitude only. The chiral volume, V(c), for chiral centers that involve a chiral atom bonded to three non-hydrogen atoms and one hydrogen atom. V~c~ = V1 * (V2 X V3) V1 = the vector distance from the atom specified by attribute atom_id in category chem_comp_chir to the first atom in the CHEM_COMP_CHIR_ATOM list V2 = the vector distance from the atom specified by attribute atom_id in category chem_comp_chir to the second atom in the CHEM_COMP_CHIR_ATOM list V3 = the vector distance from the atom specified by attribute atom_id in category chem_comp_chir to the third atom in the CHEM_COMP_CHIR_ATOM list * = the vector dot product X = the vector cross product The estimated standard deviation of attribute volume_three in category chem_comp_chir. This data item is a pointer to attribute id in category chem_comp in the CHEM_COMP category. The value of attribute id in category chem_comp_chir must uniquely identify a record in the CHEM_COMP_CHIR list. Data items in the CHEM_COMP_CHIR_ATOM category enumerate the atoms bonded to a chiral atom within a chemical component. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:chem_comp_chir_atomCategory> <RCSB:chem_comp_chir_atom atom_id="N" chir_id="1" comp_id="phe"></RCSB:chem_comp_chir_atom> <RCSB:chem_comp_chir_atom atom_id="C" chir_id="1" comp_id="phe"></RCSB:chem_comp_chir_atom> <RCSB:chem_comp_chir_atom atom_id="CB" chir_id="1" comp_id="phe"></RCSB:chem_comp_chir_atom> <RCSB:chem_comp_chir_atom atom_id="N" chir_id="1" comp_id="val"></RCSB:chem_comp_chir_atom> <RCSB:chem_comp_chir_atom atom_id="C" chir_id="1" comp_id="val"></RCSB:chem_comp_chir_atom> <RCSB:chem_comp_chir_atom atom_id="CB" chir_id="1" comp_id="val"></RCSB:chem_comp_chir_atom> </RCSB:chem_comp_chir_atomCategory> The estimated standard deviation of the position of this atom from the plane defined by all of the atoms in the plane. The id of an atom bonded to the chiral atom. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. This data item is a pointer to attribute id in category chem_comp_chir in the CHEM_COMP_CHIR category. This data item is a pointer to attribute id in category chem_comp in the CHEM_COMP category. Data items in the CHEM_COMP_LINK category give details about the linkages between chemical components. Example 1 - from nucleotide external reference dictionary Nucleic Database Project 1997. <RCSB:chem_comp_linkCategory> <RCSB:chem_comp_link link_id="ribose_adenine"> <RCSB:details> Defines the linkage between adenine base and ribose sugar</RCSB:details> <RCSB:type_comp_1>ribose</RCSB:type_comp_1> <RCSB:type_comp_2>adenine</RCSB:type_comp_2> </RCSB:chem_comp_link> </RCSB:chem_comp_linkCategory> A description of special aspects of a linkage between chemical components in the structure. The type of the first of the two components joined by the linkage. This data item is a pointer to attribute type in category chem_comp in the CHEM_COMP category. The type of the second of the two components joined by the linkage. This data item is a pointer to attribute type in category chem_comp in the CHEM_COMP category. This data item is a pointer to attribute id in category chem_link in the CHEM_LINK category. Data items in the CHEM_COMP_PLANE category provide identifiers for the planes in a chemical component. The atoms in the plane are specified in the CHEM_COMP_PLANE_ATOM category. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:chem_comp_planeCategory> <RCSB:chem_comp_plane comp_id="phe" id="phe1"></RCSB:chem_comp_plane> </RCSB:chem_comp_planeCategory> The total number of atoms in the plane. The number of non-hydrogen atoms in the plane. This data item is a pointer to attribute id in category chem_comp in the CHEM_COMP category. The value of attribute id in category chem_comp_plane must uniquely identify a record in the CHEM_COMP_PLANE list. Data items in the CHEM_COMP_PLANE_ATOM category enumerate the atoms in a plane within a chemical component. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:chem_comp_plane_atomCategory> <RCSB:chem_comp_plane_atom atom_id="CB" comp_id="phe" plane_id="phe1"></RCSB:chem_comp_plane_atom> <RCSB:chem_comp_plane_atom atom_id="CG" comp_id="phe" plane_id="phe1"></RCSB:chem_comp_plane_atom> <RCSB:chem_comp_plane_atom atom_id="CD1" comp_id="phe" plane_id="phe1"></RCSB:chem_comp_plane_atom> <RCSB:chem_comp_plane_atom atom_id="CE1" comp_id="phe" plane_id="phe1"></RCSB:chem_comp_plane_atom> <RCSB:chem_comp_plane_atom atom_id="CZ" comp_id="phe" plane_id="phe1"></RCSB:chem_comp_plane_atom> <RCSB:chem_comp_plane_atom atom_id="CE2" comp_id="phe" plane_id="phe1"></RCSB:chem_comp_plane_atom> <RCSB:chem_comp_plane_atom atom_id="CD2" comp_id="phe" plane_id="phe1"></RCSB:chem_comp_plane_atom> </RCSB:chem_comp_plane_atomCategory> This data item is the standard deviation of the out-of-plane distance for this atom. The id of an atom involved in the plane. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. This data item is a pointer to attribute id in category chem_comp in the CHEM_COMP category. This data item is a pointer to attribute id in category chem_comp_plane in the CHEM_COMP_PLANE category. Data items in the CHEM_COMP_TOR category record details about the torsion angles in a chemical component. As torsion angles can have more than one target value, the target values are specified in the CHEM_COMP_TOR_VALUE category. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:chem_comp_torCategory> <RCSB:chem_comp_tor comp_id="phe" id="phe_chi1"> <RCSB:atom_id_1>N</RCSB:atom_id_1> <RCSB:atom_id_2>CA</RCSB:atom_id_2> <RCSB:atom_id_3>CB</RCSB:atom_id_3> <RCSB:atom_id_4>CG</RCSB:atom_id_4> </RCSB:chem_comp_tor> <RCSB:chem_comp_tor comp_id="phe" id="phe_chi2"> <RCSB:atom_id_1>CA</RCSB:atom_id_1> <RCSB:atom_id_2>CB</RCSB:atom_id_2> <RCSB:atom_id_3>CG</RCSB:atom_id_3> <RCSB:atom_id_4>CD1</RCSB:atom_id_4> </RCSB:chem_comp_tor> <RCSB:chem_comp_tor comp_id="phe" id="phe_ring1"> <RCSB:atom_id_1>CB</RCSB:atom_id_1> <RCSB:atom_id_2>CG</RCSB:atom_id_2> <RCSB:atom_id_3>CD1</RCSB:atom_id_3> <RCSB:atom_id_4>CE1</RCSB:atom_id_4> </RCSB:chem_comp_tor> <RCSB:chem_comp_tor comp_id="phe" id="phe_ring2"> <RCSB:atom_id_1>CB</RCSB:atom_id_1> <RCSB:atom_id_2>CG</RCSB:atom_id_2> <RCSB:atom_id_3>CD2</RCSB:atom_id_3> <RCSB:atom_id_4>CE2</RCSB:atom_id_4> </RCSB:chem_comp_tor> <RCSB:chem_comp_tor comp_id="phe" id="phe_ring3"> <RCSB:atom_id_1>CG</RCSB:atom_id_1> <RCSB:atom_id_2>CD1</RCSB:atom_id_2> <RCSB:atom_id_3>CE1</RCSB:atom_id_3> <RCSB:atom_id_4>CZ</RCSB:atom_id_4> </RCSB:chem_comp_tor> <RCSB:chem_comp_tor comp_id="phe" id="phe_ring4"> <RCSB:atom_id_1>CD1</RCSB:atom_id_1> <RCSB:atom_id_2>CE1</RCSB:atom_id_2> <RCSB:atom_id_3>CZ</RCSB:atom_id_3> <RCSB:atom_id_4>CE2</RCSB:atom_id_4> </RCSB:chem_comp_tor> <RCSB:chem_comp_tor comp_id="phe" id="phe_ring5"> <RCSB:atom_id_1>CE1</RCSB:atom_id_1> <RCSB:atom_id_2>CZ</RCSB:atom_id_2> <RCSB:atom_id_3>CE2</RCSB:atom_id_3> <RCSB:atom_id_4>CD2</RCSB:atom_id_4> </RCSB:chem_comp_tor> </RCSB:chem_comp_torCategory> The id of the first of the four atoms that define the torsion angle. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. The id of the second of the four atoms that define the torsion angle. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. The id of the third of the four atoms that define the torsion angle. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. The id of the fourth of the four atoms that define the torsion angle. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. This data item is a pointer to attribute id in category chem_comp in the CHEM_COMP category. The value of attribute id in category chem_comp_tor must uniquely identify a record in the CHEM_COMP_TOR list. Data items in the CHEM_COMP_TOR_VALUE category record details about the target values for the torsion angles enumerated in the CHEM_COMP_TOR list. Target values may be specified as angles in degrees, as a distance between the first and fourth atoms, or both. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:chem_comp_tor_valueCategory> <RCSB:chem_comp_tor_value comp_id="phe" tor_id="phe_chi1"> <RCSB:angle>-60.0</RCSB:angle> <RCSB:dist>2.88</RCSB:dist> </RCSB:chem_comp_tor_value> <RCSB:chem_comp_tor_value comp_id="phe" tor_id="phe_chi1"> <RCSB:angle>180.0</RCSB:angle> <RCSB:dist>3.72</RCSB:dist> </RCSB:chem_comp_tor_value> <RCSB:chem_comp_tor_value comp_id="phe" tor_id="phe_chi1"> <RCSB:angle>60.0</RCSB:angle> <RCSB:dist>2.88</RCSB:dist> </RCSB:chem_comp_tor_value> <RCSB:chem_comp_tor_value comp_id="phe" tor_id="phe_chi2"> <RCSB:angle>90.0</RCSB:angle> <RCSB:dist>3.34</RCSB:dist> </RCSB:chem_comp_tor_value> <RCSB:chem_comp_tor_value comp_id="phe" tor_id="phe_chi2"> <RCSB:angle>-90.0</RCSB:angle> <RCSB:dist>3.34</RCSB:dist> </RCSB:chem_comp_tor_value> <RCSB:chem_comp_tor_value comp_id="phe" tor_id="phe_ring1"> <RCSB:angle>180.0</RCSB:angle> <RCSB:dist>3.75</RCSB:dist> </RCSB:chem_comp_tor_value> <RCSB:chem_comp_tor_value comp_id="phe" tor_id="phe_ring2"> <RCSB:angle>180.0</RCSB:angle> <RCSB:dist>3.75</RCSB:dist> </RCSB:chem_comp_tor_value> <RCSB:chem_comp_tor_value comp_id="phe" tor_id="phe_ring3"> <RCSB:angle>0.0</RCSB:angle> <RCSB:dist>2.80</RCSB:dist> </RCSB:chem_comp_tor_value> <RCSB:chem_comp_tor_value comp_id="phe" tor_id="phe_ring4"> <RCSB:angle>0.0</RCSB:angle> <RCSB:dist>2.80</RCSB:dist> </RCSB:chem_comp_tor_value> <RCSB:chem_comp_tor_value comp_id="phe" tor_id="phe_ring5"> <RCSB:angle>0.0</RCSB:angle> <RCSB:dist>2.80</RCSB:dist> </RCSB:chem_comp_tor_value> </RCSB:chem_comp_tor_valueCategory> A value that should be taken as a potential target value for the torsion angle associated with the specified atoms, expressed in degrees. The estimated standard deviation of attribute angle in category chem_comp_tor_value. A value that should be taken as a potential target value for the torsion angle associated with the specified atoms, expressed as the distance between the atoms specified by _chem_comp_tor.atom_id_1 and _chem_comp_tor.atom_id_4 in the referenced record in the CHEM_COMP_TOR list. Note that the torsion angle cannot be fully specified by a distance (for instance, a torsion angle of -60 will yield the same distance as a 60 degree angle). However the distance specification can be useful for refinement in situations in which the angle is already close to the desired value. The estimated standard deviation of attribute dist_esd in category chem_comp_tor_value. This data item is a pointer to attribute comp_id in category chem_comp_atom in the CHEM_COMP_ATOM category. This data item is a pointer to attribute id in category chem_comp_tor in the CHEM_COMP_TOR category. Data items in the CHEM_LINK category give details about the linkages between chemical groups. A description of special aspects of a linkage between chemical components in the structure. The value of attribute id in category chem_link must uniquely identify each item in the CHEM_LINK list. peptide oligosaccharide 1,4 DNA Data items in the CHEM_LINK_ANGLE category record details about angles in a linkage between chemical groups. Example 1 - Engh and Huber parameters as interpreted by J. P. Priestle <RCSB:chem_link_angleCategory> <RCSB:chem_link_angle atom_id_1="N" atom_id_2="CA" atom_id_3="C" link_id="PEPTIDE"> <RCSB:atom_1_comp_id>1</RCSB:atom_1_comp_id> <RCSB:atom_2_comp_id>1</RCSB:atom_2_comp_id> <RCSB:atom_3_comp_id>1</RCSB:atom_3_comp_id> <RCSB:value_angle>111.2</RCSB:value_angle> <RCSB:value_angle_esd>2.8</RCSB:value_angle_esd> </RCSB:chem_link_angle> <RCSB:chem_link_angle atom_id_1="CA" atom_id_2="C" atom_id_3="O" link_id="PEPTIDE"> <RCSB:atom_1_comp_id>1</RCSB:atom_1_comp_id> <RCSB:atom_2_comp_id>1</RCSB:atom_2_comp_id> <RCSB:atom_3_comp_id>1</RCSB:atom_3_comp_id> <RCSB:value_angle>120.8</RCSB:value_angle> <RCSB:value_angle_esd>1.7</RCSB:value_angle_esd> </RCSB:chem_link_angle> <RCSB:chem_link_angle atom_id_1="CA" atom_id_2="C" atom_id_3="N" link_id="PEPTIDE"> <RCSB:atom_1_comp_id>1</RCSB:atom_1_comp_id> <RCSB:atom_2_comp_id>1</RCSB:atom_2_comp_id> <RCSB:atom_3_comp_id>2</RCSB:atom_3_comp_id> <RCSB:value_angle>116.2</RCSB:value_angle> <RCSB:value_angle_esd>2.0</RCSB:value_angle_esd> </RCSB:chem_link_angle> <RCSB:chem_link_angle atom_id_1="O" atom_id_2="C" atom_id_3="N" link_id="PEPTIDE"> <RCSB:atom_1_comp_id>1</RCSB:atom_1_comp_id> <RCSB:atom_2_comp_id>1</RCSB:atom_2_comp_id> <RCSB:atom_3_comp_id>2</RCSB:atom_3_comp_id> <RCSB:value_angle>123.0</RCSB:value_angle> <RCSB:value_angle_esd>1.6</RCSB:value_angle_esd> </RCSB:chem_link_angle> <RCSB:chem_link_angle atom_id_1="C" atom_id_2="N" atom_id_3="CA" link_id="PEPTIDE"> <RCSB:atom_1_comp_id>1</RCSB:atom_1_comp_id> <RCSB:atom_2_comp_id>2</RCSB:atom_2_comp_id> <RCSB:atom_3_comp_id>2</RCSB:atom_3_comp_id> <RCSB:value_angle>121.7</RCSB:value_angle> <RCSB:value_angle_esd>1.8</RCSB:value_angle_esd> </RCSB:chem_link_angle> </RCSB:chem_link_angleCategory> This data item indicates whether atom 1 is found in the first or the second of the two components connected by the linkage. This data item indicates whether atom 2 is found in the first or the second of the two components connected by the linkage. This data item indicates whether atom 3 is found in the first or the second of the two components connected by the linkage. The value that should be taken as the target value for the angle associated with the specified atoms, expressed in degrees. The estimated standard deviation of attribute value_angle in category chem_link_angle. The value that should be taken as the target value for the angle associated with the specified atoms, expressed as the distance between the atoms specified by attribute atom_id_1 in category chem_comp_angle and attribute atom_id_3 in category chem_comp_angle. The estimated standard deviation of attribute value_dist_esd in category chem_comp_angle. The id of the first of the three atoms that define the angle. An atom with this id must exist in the component of the type specified by _chem_comp_link.type_1 (or _chem_comp_link.type_2, where the appropriate data item is indated by the value of attribute atom_1_comp_id) in category chem_comp_link. The id of the second of the three atoms that define the angle. The second atom is taken to be the apex of the angle. An atom with this id must exist in the component of the type specified by _chem_comp_link.type_1 (or _chem_comp_link.type_2, where the appropriate data item is indated by the value of attribute atom_2_comp_id) in category chem_comp_link. The id of the third of the three atoms that define the angle. An atom with this id must exist in the component of the type specified by _chem_comp_link.type_1 (or _chem_comp_link.type_2, where the appropriate data item is indated by the value of attribute atom_3_comp_id) in category chem_comp_link. This data item is a pointer to attribute id in category chem_link in the CHEM_LINK category. Data items in the CHEM_LINK_BOND category record details about bonds in a linkage between components in the chemical structure. Example 1 - Engh and Huber parameters as interpreted by J. P. Priestle <RCSB:chem_link_bondCategory> <RCSB:chem_link_bond atom_id_1="N" atom_id_2="CA" link_id="PEPTIDE"> <RCSB:atom_1_comp_id>1</RCSB:atom_1_comp_id> <RCSB:atom_2_comp_id>1</RCSB:atom_2_comp_id> <RCSB:value_dist>1.458</RCSB:value_dist> <RCSB:value_dist_esd>0.019</RCSB:value_dist_esd> </RCSB:chem_link_bond> <RCSB:chem_link_bond atom_id_1="CA" atom_id_2="C" link_id="PEPTIDE"> <RCSB:atom_1_comp_id>1</RCSB:atom_1_comp_id> <RCSB:atom_2_comp_id>1</RCSB:atom_2_comp_id> <RCSB:value_dist>1.525</RCSB:value_dist> <RCSB:value_dist_esd>0.021</RCSB:value_dist_esd> </RCSB:chem_link_bond> <RCSB:chem_link_bond atom_id_1="C" atom_id_2="N" link_id="PEPTIDE"> <RCSB:atom_1_comp_id>1</RCSB:atom_1_comp_id> <RCSB:atom_2_comp_id>2</RCSB:atom_2_comp_id> <RCSB:value_dist>1.329</RCSB:value_dist> <RCSB:value_dist_esd>0.014</RCSB:value_dist_esd> </RCSB:chem_link_bond> <RCSB:chem_link_bond atom_id_1="C" atom_id_2="O" link_id="PEPTIDE"> <RCSB:atom_1_comp_id>1</RCSB:atom_1_comp_id> <RCSB:atom_2_comp_id>1</RCSB:atom_2_comp_id> <RCSB:value_dist>1.231</RCSB:value_dist> <RCSB:value_dist_esd>0.020</RCSB:value_dist_esd> </RCSB:chem_link_bond> </RCSB:chem_link_bondCategory> This data item indicates whether atom 1 is found in the first or the second of the two components connected by the linkage. This data item indicates whether atom 2 is found in the first or the second of the two chemical components connected by the linkage. The value that should be taken as the target for the chemical bond associated with the specified atoms, expressed as a distance. The estimated standard deviation of attribute value_dist_esd in category chem_link_bond. The value that should be taken as the target for the chemical bond associated with the specified atoms, expressed as a bond order. The id of the first of the two atoms that define the bond. As this data item does not point to a specific atom in a specific chemical component, it is not a child in the linkage sense. The id of the second of the two atoms that define the bond. As this data item does not point to a specific atom in a specific component, it is not a child in the linkage sense. This data item is a pointer to attribute id in category chem_link in the CHEM_LINK category. Data items in the CHEM_LINK_CHIR category provide detail about the chiral centers in a linkage between two chemical components. The atoms bonded to the chiral atom are specified in the CHEM_LINK_CHIR_ATOM category. Example 1 - based on This data item indicates whether the chiral atom is found in the first or the second of the two component connected by the linkage. The chiral configuration of the atom that is a chiral center. The id of the atom that is a chiral center. As this data item does not point to a specific atom in a specific chemical component, it is not a child in the linkage sense. The total number of atoms bonded to the atom specified by attribute atom_id in category chem_link_chir. The number of non-hydrogen atoms bonded to the atom specified by attribute atom_id in category chem_link_chir. A flag to indicate whether a chiral volume should match the standard value in both magnitude and sign, or in magnitude only. The chiral volume, V(c), for chiral centers that involve a chiral atom bonded to three non-hydrogen atoms and one hydrogen atom. V~c~ = V1 * (V2 X V3) V1 = the vector distance from the atom specified by attribute atom_id in category chem_link_chir to the first atom in the CHEM_LINK_CHIR_ATOM list V2 = the vector distance from the atom specified by attribute atom_id in category chem_link_chir to the second atom in the CHEM_LINK_CHIR_ATOM list V3 = the vector distance from the atom specified by attribute atom_id in category chem_link_chir to the third atom in the CHEM_LINK_CHIR_ATOM list * = the vector dot product X = the vector cross product The estimated standard deviation of attribute volume_three in category chem_link_chir. The value of attribute id in category chem_link_chir must uniquely identify a record in the CHEM_LINK_CHIR list. This data item is a pointer to attribute id in category chem_link in the CHEM_LINK category. Data items in the CHEM_LINK_CHIR_ATOM category enumerate the atoms bonded to a chiral atom in a linkage between two chemical components. Example 1 - based on This data item indicates whether the atom bonded to a chiral atom is found in the first or the second of the two components connected by the linkage. The estimated standard deviation of the position of this atom from the plane defined by all of the atoms in the plane. The id of an atom bonded to the chiral atom. As this data item does not point to a specific atom in a specific chemical component, it is not a child in the linkage sense. This data item is a pointer to attribute id in category chem_link_chir in the CHEM_LINK_CHIR category. Data items in the CHEM_LINK_PLANE category provide identifiers for the planes in a linkage between two chemical components. The atoms in the plane are specified in the CHEM_LINK_PLANE_ATOM category. Example 1 - based on The total number of atoms in the plane. The number of non-hydrogen atoms in the plane. The value of attribute id in category chem_link_plane must uniquely identify a record in the CHEM_LINK_PLANE list. This data item is a pointer to attribute id in category chem_link in the CHEM_LINK category. Data items in the CHEM_LINK_PLANE_ATOM category enumerate the atoms in a plane in a linkage between two chemical components. Example 1 - based on This data item indicates whether the atom in a plane is found in the first or the second of the two components connected by the linkage. The id of an atom involved in the plane. As this data item does not point to a specific atom in a specific chemical component, it is not a child in the linkage sense. This data item is a pointer to attribute id in category chem_link_plane in the CHEM_LINK_PLANE category. Data items in the CHEM_LINK_TOR category record details about the torsion angles in a linkage between two chemical components. As torsion angles can have more than one target value, the target values are specified in the CHEM_LINK_TOR_VALUE category. Example 1 - based on This data item indicates whether atom 1 is found in the first or the second of the two components connected by the linkage. This data item indicates whether atom 2 is found in the first or the second of the two components connected by the linkage. This data item indicates whether atom 3 is found in the first or the second of the two components connected by the linkage. This data item indicates whether atom 4 is found in the first or the second of the two components connected by the linkage. The id of the first of the four atoms that define the torsion angle. As this data item does not point to a specific atom in a specific chemical component, it is not a child in the linkage sense. The id of the second of the four atoms that define the torsion angle. As this data item does not point to a specific atom in a specific chemical component, it is not a child in the linkage sense. The id of the third of the four atoms that define the torsion angle. As this data item does not point to a specific atom in a specific chemical component, it is not a child in the linkage sense. The id of the fourth of the four atoms that define the torsion angle. As this data item does not point to a specific atom in a specific chemical component, it is not a child in the linkage sense. The value of attribute id in category chem_link_tor must uniquely identify a record in the CHEM_LINK_TOR list. This data item is a pointer to attribute id in category chem_link in the CHEM_LINK category. Data items in the CHEM_LINK_TOR_VALUE category record details about the target values for the torsion angles enumerated in the CHEM_LINK_TOR list. Target values may be specified as angles in degrees, as a distance between the first and fourth atoms, or both. Example 1 - based on A value that should be taken as a potential target value for the torsion angle associated with the specified atoms, expressed in degrees. The estimated standard deviation of attribute angle in category chem_link_tor_value. A value that should be taken as a potential target value for the torsion angle associated with the specified atoms, expressed as the distance between the atoms specified by _chem_link_tor.atom_id_1 and _chem_link_tor.atom_id_4 in the referenced record in the CHEM_LINK_TOR list. Note that the torsion angle cannot be fully specified by a distance (for instance, a torsion angle of -60 will yield the same distance as a 60 degree angle). However the distance specification can be useful for refinement in situations in which the angle is already close to the desired value. The estimated standard deviation of attribute dist_esd in category chem_link_tor_value. This data item is a pointer to attribute id in category chem_link_tor in the CHEM_LINK_TOR category. Data items in the CHEMICAL category would not in general be used in a macromolecular CIF. See instead the ENTITY data items. Data items in the CHEMICAL category record details about the composition and chemical properties of the compounds. The formula data items must agree with those that specify the density, unit-cell and Z values. Example 1 - based on data set 9597gaus of Alyea, Ferguson & Kannan [(1996). Acta Cryst. C52, 765-767]. <RCSB:chemicalCategory> <RCSB:chemical entry_id="9597gaus"> <RCSB:name_systematic>trans-bis(tricyclohexylphosphine)tetracarbonylmolybdenum(0)</RCSB:name_systematic> </RCSB:chemical> </RCSB:chemicalCategory> Description of the source of the compound under study, or of the parent molecule if a simple derivative is studied. This includes the place of discovery for minerals or the actual source of a natural product. From Norilsk (USSR) Extracted from the bark of Cinchona Naturalis The temperature in kelvins at which a crystalline solid changes to a liquid. Trivial name by which the compound is commonly known. 1-bromoestradiol Mineral name accepted by the International Mineralogical Association. Use only for natural minerals. See also attribute compound_source in category chemical. chalcopyrite Commonly used structure-type name. Usually only applied to minerals or inorganic compounds. perovskite sphalerite A15 IUPAC or Chemical Abstracts full name of compound. 1-bromoestra-1,3,5(10)-triene-3,17\b-diol This data item is a pointer to attribute id in category entry in the ENTRY category. Data items in the CHEMICAL_CONN_ATOM category would not, in general, be used in a macromolecular CIF. See instead the ENTITY data items. Data items in the CHEMICAL_CONN_ATOM and CHEMICAL_CONN_BOND categories record details about the 2D chemical structure of the molecular species. They allow a 2D chemical diagram to be reconstructed for use in a publication or in a database search for structural and substructural relationships. The CHEMICAL_CONN_ATOM data items provide information about the chemical properties of the atoms in the structure. In cases where crystallographic and molecular symmetry elements coincide they must also contain symmetry-generated atoms, so that the CHEMICAL_CONN_ATOM and CHEMICAL_CONN_BOND data items will always describe a complete chemical entity. Example 1 - based on data set DPTD of Yamin, Suwandi, Fun, Sivakumar & bin Shawkataly [(1996). Acta Cryst. C52, 951-953]. <RCSB:chemical_conn_atomCategory> <RCSB:chemical_conn_atom number="1"> <RCSB:NCA>1</RCSB:NCA> <RCSB:NH>0</RCSB:NH> <RCSB:display_x>.39</RCSB:display_x> <RCSB:display_y>.81</RCSB:display_y> <RCSB:type_symbol>S</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="2"> <RCSB:NCA>2</RCSB:NCA> <RCSB:NH>0</RCSB:NH> <RCSB:display_x>.39</RCSB:display_x> <RCSB:display_y>.96</RCSB:display_y> <RCSB:type_symbol>S</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="3"> <RCSB:NCA>3</RCSB:NCA> <RCSB:NH>0</RCSB:NH> <RCSB:display_x>.14</RCSB:display_x> <RCSB:display_y>.88</RCSB:display_y> <RCSB:type_symbol>N</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="4"> <RCSB:NCA>3</RCSB:NCA> <RCSB:NH>0</RCSB:NH> <RCSB:display_x>.33</RCSB:display_x> <RCSB:display_y>.88</RCSB:display_y> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="5"> <RCSB:NCA>2</RCSB:NCA> <RCSB:NH>2</RCSB:NH> <RCSB:display_x>.11</RCSB:display_x> <RCSB:display_y>.96</RCSB:display_y> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="6"> <RCSB:NCA>2</RCSB:NCA> <RCSB:NH>2</RCSB:NH> <RCSB:display_x>.03</RCSB:display_x> <RCSB:display_y>.96</RCSB:display_y> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="7"> <RCSB:NCA>2</RCSB:NCA> <RCSB:NH>2</RCSB:NH> <RCSB:display_x>.03</RCSB:display_x> <RCSB:display_y>.80</RCSB:display_y> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="8"> <RCSB:NCA>2</RCSB:NCA> <RCSB:NH>2</RCSB:NH> <RCSB:display_x>.11</RCSB:display_x> <RCSB:display_y>.80</RCSB:display_y> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="9"> <RCSB:NCA>1</RCSB:NCA> <RCSB:NH>0</RCSB:NH> <RCSB:display_x>.54</RCSB:display_x> <RCSB:display_y>.81</RCSB:display_y> <RCSB:type_symbol>S</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="10"> <RCSB:NCA>2</RCSB:NCA> <RCSB:NH>0</RCSB:NH> <RCSB:display_x>.54</RCSB:display_x> <RCSB:display_y>.96</RCSB:display_y> <RCSB:type_symbol>S</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="11"> <RCSB:NCA>3</RCSB:NCA> <RCSB:NH>0</RCSB:NH> <RCSB:display_x>.80</RCSB:display_x> <RCSB:display_y>.88</RCSB:display_y> <RCSB:type_symbol>N</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="12"> <RCSB:NCA>3</RCSB:NCA> <RCSB:NH>0</RCSB:NH> <RCSB:display_x>.60</RCSB:display_x> <RCSB:display_y>.88</RCSB:display_y> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="13"> <RCSB:NCA>2</RCSB:NCA> <RCSB:NH>2</RCSB:NH> <RCSB:display_x>.84</RCSB:display_x> <RCSB:display_y>.96</RCSB:display_y> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="14"> <RCSB:NCA>2</RCSB:NCA> <RCSB:NH>2</RCSB:NH> <RCSB:display_x>.91</RCSB:display_x> <RCSB:display_y>.96</RCSB:display_y> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="15"> <RCSB:NCA>2</RCSB:NCA> <RCSB:NH>2</RCSB:NH> <RCSB:display_x>.91</RCSB:display_x> <RCSB:display_y>.80</RCSB:display_y> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chemical_conn_atom> <RCSB:chemical_conn_atom number="16"> <RCSB:NCA>2</RCSB:NCA> <RCSB:NH>2</RCSB:NH> <RCSB:display_x>.84</RCSB:display_x> <RCSB:display_y>.80</RCSB:display_y> <RCSB:type_symbol>C</RCSB:type_symbol> </RCSB:chemical_conn_atom> </RCSB:chemical_conn_atomCategory> The number of connected atoms excluding terminal hydrogen atoms. The total number of hydrogen atoms attached to this atom, regardless of whether they are included in the refinement or the ATOM_SITE list. This number is the same as attribute attached_hydrogens in category atom_site only if none of the hydrogen atoms appear in the ATOM_SITE list. The net integer charge assigned to this atom. This is the formal charge assignment normally found in chemical diagrams. for an ammonium nitrogen 1 for a chloride ion -1 The 2D Cartesian x coordinate of the position of this atom in a recognisable chemical diagram. The coordinate origin is at the lower left corner, the x axis is horizontal and the y axis is vertical. The coordinates must lie in the range 0.0 to 1.0. These coordinates can be obtained from projections of a suitable uncluttered view of the molecular structure. If absent, values will be assigned by the journal or database staff. The 2D Cartesian y coordinate of the position of this atom in a recognisable chemical diagram. The coordinate origin is at the lower left corner, the x axis is horizontal and the y axis is vertical. The coordinates must lie in the range 0.0 to 1.0. These coordinates can be obtained from projections of a suitable uncluttered view of the molecular structure. If absent, values will be assigned by the journal or database staff. This data item is a pointer to attribute symbol in category atom_type in the ATOM_TYPE category. The chemical sequence number to be associated with this atom. Within an ATOM_SITE list this number must match with one of the attribute chemical_conn_number in category atom_site values. Data items in the CHEMICAL_CONN_BOND category would not, in general, be used in a macromolecular CIF. See instead the ENTITY data items. Data items in the CHEMICAL_CONN_ATOM and CHEMICAL_CONN_BOND categories record details about the 2D chemical structure of the molecular species. They allow a 2D chemical diagram to be reconstructed for use in a publication or in a database search for structural and substructural relationships. The CHEMICAL_CONN_BOND data items specify the connections between the atoms in the CHEMICAL_CONN_ATOM list and the nature of the chemical bond between these atoms. Example 1 - based on data set DPTD of Yamin, Suwandi, Fun, Sivakumar & bin Shawkataly [(1996). Acta Cryst. C52, 951-953]. <RCSB:chemical_conn_bondCategory> <RCSB:chemical_conn_bond atom_1="4" atom_2="1"> <RCSB:type>doub</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="4" atom_2="3"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="4" atom_2="2"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="5" atom_2="3"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="6" atom_2="5"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="7" atom_2="6"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="8" atom_2="7"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="8" atom_2="3"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="10" atom_2="2"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="12" atom_2="9"> <RCSB:type>doub</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="12" atom_2="11"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="12" atom_2="10"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="13" atom_2="11"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="14" atom_2="13"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="15" atom_2="14"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="16" atom_2="15"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="16" atom_2="11"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="17" atom_2="5"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="18" atom_2="5"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="19" atom_2="6"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="20" atom_2="6"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="21" atom_2="7"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="22" atom_2="7"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="23" atom_2="8"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="24" atom_2="8"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="25" atom_2="13"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="26" atom_2="13"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="27" atom_2="14"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="28" atom_2="14"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="29" atom_2="15"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="30" atom_2="15"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="31" atom_2="16"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> <RCSB:chemical_conn_bond atom_1="32" atom_2="16"> <RCSB:type>sing</RCSB:type> </RCSB:chemical_conn_bond> </RCSB:chemical_conn_bondCategory> The chemical bond type associated with the connection between the two sites attribute atom_1 in category chemical_conn_bond and attribute atom_2 in category chemical_conn_bond. This data item is a pointer to attribute number in category chemical_conn_atom in the CHEMICAL_CONN_ATOM category. This data item is a pointer to attribute number in category chemical_conn_atom in the CHEMICAL_CONN_ATOM category. Data items in the CHEMICAL_FORMULA category would not, in general, be used in a macromolecular CIF. See instead the ENTITY data items. Data items in the CHEMICAL_FORMULA category specify the composition and chemical properties of the compound. The formula data items must agree with those that specify the density, unit cell and Z values. The following rules apply to the construction of the data items _chemical_formula.analytical, _chemical_formula.structural and attribute sum in category chemical_formula. For the data item attribute moiety in category chemical_formula the formula construction is broken up into residues or moieties, i.e. groups of atoms that form a molecular unit or molecular ion. The rules given below apply within each moiety but different requirements apply to the way that moieties are connected (see attribute moiety). in category chemical_formula 1. Only recognised element symbols may be used. 2. Each element symbol is followed by a 'count' number. A count of '1' may be omitted. 3. A space or parenthesis must separate each cluster of (element symbol + count). 4. Where a group of elements is enclosed in parentheses, the multiplier for the group must follow the closing parentheses. That is, all element and group multipliers are assumed to be printed as subscripted numbers. [An exception to this rule exists for attribute moiety in category chemical_formula formulae where pre- and post-multipliers are permitted for molecular units]. 5. Unless the elements are ordered in a manner that corresponds to their chemical structure, as in attribute structural in category chemical_formula the order of the elements within any group or moiety should be: C, H followed by the other elements in alphabetical order of their symbol. This is the 'Hill' system used by Chemical Abstracts. This ordering is used in _chemical_formula.moiety and _chemical_formula.sum. Example 2 - based on data set TOZ of Willis, Beckwith & Tozer [(1991). Acta Cryst. C47, 2276-2277]. <RCSB:chemical_formulaCategory> <RCSB:chemical_formula entry_id="TOZ"> <RCSB:moiety>C18 H25 N O3</RCSB:moiety> <RCSB:sum>C18 H25 N O3</RCSB:sum> <RCSB:weight>303.40</RCSB:weight> </RCSB:chemical_formula> </RCSB:chemical_formulaCategory> Formula determined by standard chemical analysis including trace elements. See the CHEMICAL_FORMULA category description for rules for writing chemical formulae. Parentheses are used only for standard uncertainties (e.s.d.'s). Fe2.45(2) Ni1.60(3) S4 Formula expressed in conformance with IUPAC rules for inorganic and metal-organic compounds where these conflict with the rules for any other CHEMICAL_FORMULA entries. Typically used for formatting a formula in accordance with journal rules. This should appear in the data block in addition to the most appropriate of the other CHEMICAL_FORMULA data names. Ref: IUPAC (1990). Nomenclature of Inorganic Chemistry. Oxford: Blackwell Scientific Publications. [Co Re (C12 H22 P)2 (C O)6].0.5C H3 O H Formula with each discrete bonded residue or ion shown as a separate moiety. See the CHEMICAL_FORUMULA category description for rules for writing chemical formulae. In addition to the general formulae requirements, the following rules apply: 1. Moieties are separated by commas ','. 2. The order of elements within a moiety follows general rule 5 in the CHEMICAL_FORMULA category description. 3. Parentheses are not used within moieties but may surround a moiety. Parentheses may not be nested. 4. Charges should be placed at the end of the moiety. The charge '+' or '-' may be preceded by a numerical multiplier and should be separated from the last (element symbol + count) by a space. Pre- or post-multipliers may be used for individual moieties. C7 H4 Cl Hg N O3 S C12 H17 N4 O S 1+, C6 H2 N3 O7 1- C12 H16 N2 O6, 5(H2 O1) (Cd 2+)3, (C6 N6 Cr 3-)2, 2(H2 O) See the CHEMICAL_FORMULA category description for the rules for writing chemical formulae for inorganics, organometallics, metal complexes etc., in which bonded groups are preserved as discrete entities within parentheses, with post-multipliers as required. The order of the elements should give as much information as possible about the chemical structure. Parentheses may be used and nested as required. This formula should correspond to the structure as actually reported, i.e. trace elements not included in atom type and atom site data should not be included in this formula (see also attribute analytical) in category chemical_formula. Ca ((Cl O3)2 O)2 (H2 O)6 (Pt (N H3)2 (C5 H7 N3 O)2) (Cl O4)2 See the CHEMICAL_FORMULA category description for the rules for writing chemical formulae in which all discrete bonded residues and ions are summed over the constituent elements, following the ordering given in general rule 5 in the CHEMICAL_FORMULA category description. Parentheses are not normally used. C18 H19 N7 O8 S Formula mass in daltons. This mass should correspond to the formulae given under attribute structural in category chemical_formula chemical_formula.moiety or attribute sum in category chemical_formula and, together with the Z value and cell parameters, should yield the density given as attribute density_diffrn in category exptl_crystal. Formula mass in daltons measured by a non-diffraction experiment. This data item is a pointer to attribute id in category entry in the ENTRY category. Data items in the CITATION category record details about the literature cited relevant to the contents of the data block. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:citationCategory> <RCSB:citation id="primary"> <RCSB:book_id_ISBN></RCSB:book_id_ISBN> <RCSB:book_publisher></RCSB:book_publisher> <RCSB:book_title></RCSB:book_title> <RCSB:coordinate_linkage>yes</RCSB:coordinate_linkage> <RCSB:country>US</RCSB:country> <RCSB:details> The publication that directly relates to this coordinate set.</RCSB:details> <RCSB:journal_abbrev>J. Biol. Chem.</RCSB:journal_abbrev> <RCSB:journal_id_ASTM>HBCHA3</RCSB:journal_id_ASTM> <RCSB:journal_id_CSD>071</RCSB:journal_id_CSD> <RCSB:journal_id_ISSN>0021-9258</RCSB:journal_id_ISSN> <RCSB:journal_issue></RCSB:journal_issue> <RCSB:journal_volume>265</RCSB:journal_volume> <RCSB:page_first>14209</RCSB:page_first> <RCSB:page_last>14219</RCSB:page_last> <RCSB:title> Crystallographic analysis of a complex between human immunodeficiency virus type 1 protease and acetyl-pepstatin at 2.0-Angstroms resolution.</RCSB:title> <RCSB:year>1990</RCSB:year> </RCSB:citation> <RCSB:citation id="2"> <RCSB:book_id_ISBN></RCSB:book_id_ISBN> <RCSB:book_publisher></RCSB:book_publisher> <RCSB:book_title></RCSB:book_title> <RCSB:coordinate_linkage>no</RCSB:coordinate_linkage> <RCSB:country>UK</RCSB:country> <RCSB:details> Determination of the structure of the unliganded enzyme.</RCSB:details> <RCSB:journal_abbrev>Nature</RCSB:journal_abbrev> <RCSB:journal_id_ASTM>NATUAS</RCSB:journal_id_ASTM> <RCSB:journal_id_CSD>006</RCSB:journal_id_CSD> <RCSB:journal_id_ISSN>0028-0836</RCSB:journal_id_ISSN> <RCSB:journal_issue></RCSB:journal_issue> <RCSB:journal_volume>337</RCSB:journal_volume> <RCSB:page_first>615</RCSB:page_first> <RCSB:page_last>619</RCSB:page_last> <RCSB:title> Three-dimensional structure of aspartyl-protease from human immunodeficiency virus HIV-1.</RCSB:title> <RCSB:year>1989</RCSB:year> </RCSB:citation> <RCSB:citation id="3"> <RCSB:book_id_ISBN></RCSB:book_id_ISBN> <RCSB:book_publisher></RCSB:book_publisher> <RCSB:book_title></RCSB:book_title> <RCSB:coordinate_linkage>no</RCSB:coordinate_linkage> <RCSB:country>US</RCSB:country> <RCSB:details> Crystallization of the unliganded enzyme.</RCSB:details> <RCSB:journal_abbrev>J. Biol. Chem.</RCSB:journal_abbrev> <RCSB:journal_id_ASTM>HBCHA3</RCSB:journal_id_ASTM> <RCSB:journal_id_CSD>071</RCSB:journal_id_CSD> <RCSB:journal_id_ISSN>0021-9258</RCSB:journal_id_ISSN> <RCSB:journal_issue></RCSB:journal_issue> <RCSB:journal_volume>264</RCSB:journal_volume> <RCSB:page_first>1919</RCSB:page_first> <RCSB:page_last>1921</RCSB:page_last> <RCSB:title> Crystallization of the aspartylprotease from human immunodeficiency virus, HIV-1.</RCSB:title> <RCSB:year>1989</RCSB:year> </RCSB:citation> <RCSB:citation id="4"> <RCSB:book_id_ISBN></RCSB:book_id_ISBN> <RCSB:book_publisher></RCSB:book_publisher> <RCSB:book_title></RCSB:book_title> <RCSB:coordinate_linkage>no</RCSB:coordinate_linkage> <RCSB:country>US</RCSB:country> <RCSB:details> Expression and purification of the enzyme.</RCSB:details> <RCSB:journal_abbrev>J. Biol. Chem.</RCSB:journal_abbrev> <RCSB:journal_id_ASTM>HBCHA3</RCSB:journal_id_ASTM> <RCSB:journal_id_CSD>071</RCSB:journal_id_CSD> <RCSB:journal_id_ISSN>0021-9258</RCSB:journal_id_ISSN> <RCSB:journal_issue></RCSB:journal_issue> <RCSB:journal_volume>264</RCSB:journal_volume> <RCSB:page_first>2307</RCSB:page_first> <RCSB:page_last>2312</RCSB:page_last> <RCSB:title> Human immunodeficiency virus protease. Bacterial expression and characterization of the purified aspartic protease.</RCSB:title> <RCSB:year>1989</RCSB:year> </RCSB:citation> </RCSB:citationCategory> Abstract for the citation. This is used most when the citation is extracted from a bibliographic database that contains full text or abstract information. The Chemical Abstracts Service (CAS) abstract identifier; relevant for journal articles. The International Standard Book Number (ISBN) code assigned to the book cited; relevant for book chapters. The name of the publisher of the citation; relevant for book chapters. John Wiley and Sons The location of the publisher of the citation; relevant for book chapters. London The title of the book in which the citation appeared; relevant for book chapters. attribute coordinate_linkage in category citation states whether or not this citation is concerned with precisely the set of coordinates given in the data block. If, for instance, the publication described the same structure, but the coordinates had undergone further refinement prior to creation of the data block, the value of this data item would be 'no'. The country of publication; relevant for both journal articles and book chapters. Ascession number used by Medline to categorize a specific bibliographic entry. 89064067 A description of special aspects that describe the relationship of the contents of the data block to the literature item cited. citation relates to this precise coordinate set citation relates to earlier low-resolution structure citation relates to further refinement of structure reported in citation 2 Abbreviated name of the journal cited as given in the Chemical Abstracts Service Source Index. J. Mol. Biol. Full name of the journal cited; relevant for journal articles. Journal of Molecular Biology The American Society for the Testing of Materials (ASTM) code assigned to the journal cited (also referred to as the CODEN designator of the Chemical Abstracts Service); relevant for journal articles. The Cambridge Structural Database (CSD) code assigned to the journal cited; relevant for journal articles. This is also the system used at the Brookhaven Protein Data Bank (PDB). 070 The International Standard Serial Number (ISSN) code assigned to the journal cited; relevant for journal articles. Issue number of the journal cited; relevant for journal articles. 2 Volume number of the journal cited; relevant for journal articles. 174 Language in which the citation appears. german List of the names of authors of the citation. Intials or first names followed by family name(s). Multiple authors separated by commas or by the word 'and'. B. H. M. Mooers, B. F. Eichman and P. S. Ho D. B. Tippin and M. Sundaralingam The first page of the citation; relevant for journal articles and book chapters. The last page of the citation; relevant for journal articles and book chapters. Document Object Identifier used by doi.org to uniquely specify bibliographic entry. DOI:10.2345/S1384107697000225 Ascession number used by PubMed to categorize a specific bibliographic entry. 12627512 The title of the citation; relevant for both journal articles and book chapters. Structure of Diferric Duck Ovatransferrin at 2.35 \%A Resolution. Flag to indicate that this citation will not be published. The year of the citation; relevant for both journal articles and book chapters. 1984 The value of attribute id in category citation must uniquely identify a record in the CITATION list. The attribute id in category citation 'primary' should be used to indicate the citation that the author(s) consider to be the most pertinent to the contents of the data block. Note that this item need not be a number; it can be any unique identifier. primary 1 2 Data items in the CITATION_AUTHOR category record details about the authors associated with the citations in the CITATION list. Example 1 - based on PDB entry 5HVP and/or laboratory records for the structure corresponding to PDB entry 5HVP <RCSB:citation_authorCategory> <RCSB:citation_author citation_id="primary" name="Fitzgerald, P.M.D." ordinal="1"></RCSB:citation_author> <RCSB:citation_author citation_id="primary" name="McKeever, B.M." ordinal="2"></RCSB:citation_author> <RCSB:citation_author citation_id="primary" name="Van Middlesworth, J.F." ordinal="3"></RCSB:citation_author> <RCSB:citation_author citation_id="primary" name="Springer, J.P." ordinal="4"></RCSB:citation_author> <RCSB:citation_author citation_id="primary" name="Heimbach, J.C." ordinal="5"></RCSB:citation_author> <RCSB:citation_author citation_id="primary" name="Leu, C.-T." ordinal="6"></RCSB:citation_author> <RCSB:citation_author citation_id="primary" name="Herber, W.K." ordinal="7"></RCSB:citation_author> <RCSB:citation_author citation_id="primary" name="Dixon, R.A.F." ordinal="8"></RCSB:citation_author> <RCSB:citation_author citation_id="primary" name="Darke, P.L." ordinal="9"></RCSB:citation_author> <RCSB:citation_author citation_id="2" name="Navia, M.A." ordinal="1"></RCSB:citation_author> <RCSB:citation_author citation_id="2" name="Fitzgerald, P.M.D." ordinal="2"></RCSB:citation_author> <RCSB:citation_author citation_id="2" name="McKeever, B.M." ordinal="3"></RCSB:citation_author> <RCSB:citation_author citation_id="2" name="Leu, C.-T." ordinal="4"></RCSB:citation_author> <RCSB:citation_author citation_id="2" name="Heimbach, J.C." ordinal="5"></RCSB:citation_author> <RCSB:citation_author citation_id="2" name="Herber, W.K." ordinal="6"></RCSB:citation_author> <RCSB:citation_author citation_id="2" name="Sigal, I.S." ordinal="7"></RCSB:citation_author> <RCSB:citation_author citation_id="2" name="Darke, P.L." ordinal="8"></RCSB:citation_author> <RCSB:citation_author citation_id="2" name="Springer, J.P." ordinal="9"></RCSB:citation_author> <RCSB:citation_author citation_id="3" name="McKeever, B.M." ordinal="1"></RCSB:citation_author> <RCSB:citation_author citation_id="3" name="Navia, M.A." ordinal="2"></RCSB:citation_author> <RCSB:citation_author citation_id="3" name="Fitzgerald, P.M.D." ordinal="3"></RCSB:citation_author> <RCSB:citation_author citation_id="3" name="Springer, J.P." ordinal="4"></RCSB:citation_author> <RCSB:citation_author citation_id="3" name="Leu, C.-T." ordinal="5"></RCSB:citation_author> <RCSB:citation_author citation_id="3" name="Heimbach, J.C." ordinal="6"></RCSB:citation_author> <RCSB:citation_author citation_id="3" name="Herber, W.K." ordinal="7"></RCSB:citation_author> <RCSB:citation_author citation_id="3" name="Sigal, I.S." ordinal="8"></RCSB:citation_author> <RCSB:citation_author citation_id="3" name="Darke, P.L." ordinal="9"></RCSB:citation_author> <RCSB:citation_author citation_id="4" name="Darke, P.L." ordinal="1"></RCSB:citation_author> <RCSB:citation_author citation_id="4" name="Leu, C.-T." ordinal="2"></RCSB:citation_author> <RCSB:citation_author citation_id="4" name="Davis, L.J." ordinal="3"></RCSB:citation_author> <RCSB:citation_author citation_id="4" name="Heimbach, J.C." ordinal="4"></RCSB:citation_author> <RCSB:citation_author citation_id="4" name="Diehl, R.E." ordinal="5"></RCSB:citation_author> <RCSB:citation_author citation_id="4" name="Hill, W.S." ordinal="6"></RCSB:citation_author> <RCSB:citation_author citation_id="4" name="Dixon, R.A.F